Posts Tagged ‘alternative’

Linux show largest sized packages / Which Deb, RPM Linux installed package use most disk space and How to Free Space for critical system updates

Sunday, January 12th, 2020


A very common problem that happens on both Linux installed servers and Desktop Linux is a starting to fill / (root partition). This problem could happen due to several reasons just to point few of them out of my experience low disk space (ending free space) could be due to:

– Improper initial partitioning / bad space planning / or OS install made in a hurry (due to time constrains)
– Linux installed on old laptop machine with low Hard Disk Drive capacity (e.g. 80 Giga / 160 GB)
– Custom user partitioning on install time aiming for a small root partition originally and changing space requirements in time
– Due to increasing space taken by Linux updates / user stored files etc / distribution OS Level upgrades dist-upgrades.
– Improperly assigned install time partitions cause of lack of knowledge to understand how partitioning is managed.
– Due to install being made in a hurry

– Linux OS installed on a Cloud based VPN (e.g. running) in a Cloud Instance that is hosted in Amazon EC2, Linode, Digital Ocean, Hostgator etc.

So here is a real time situation that happened me many times, you're launching an apt-get upgrade / apt-get dist-upgrade or yum upgrade the packages are about to start downloading or downloaded and suddenly you get a message of not enough disk space to apply OS package updates …
That's nasty stuff mostly irritating and here there are few approaches to take.

a. perhaps easiest you can ofcourse extend the partition (with a free spaced other Primary or Extended partition) with something like:

parted (the disk partitioning manipulator for Linux), gparted (in case if Desktop with GUI / XOrg server running)

b. if not enough space on the Hard Disk Drive or SSD (Solid State Drive) and you have a budget to buy and free laptop / PC slot to place another physical HDD to clone it to a larger sized HDD and use some kind of partition clone tool, such as:

or any of the other multiple clone tools available in Linux.

But what if you don't have the option for some reason to extend the paritiotn, how can you apply the Critical Security Errata Updates issued to patch security vulnerabilities reported by well known CVEs?
Well you can start with the obvious easy you can start removing unnecessery stuff from the system (if home is also stored on the / – root partiiton) to delete something from there, even delete the /usr/local/man pages if you don't plan to read it free some logs by archiving purging logs from /var/log/* …

But if this is not possible, a better approach is simply try to remove / purge any .deb / .rpm whatever distro package manager packages that are not necessery used and just hanging around, that is often the case especially on Linux installed on Notebooks for a personal home use, where with years you have installed a growing number of packages which you don't actively use but installed just to take a look, while hunting for Cool Linux games and you wanted to give a try to Battle of Wesnoth  / FreeCIV / AlienArena / SuperTux Kart / TuxRacer etc.  or some GUI heavy programs like Krita / Inskape / Audacity etc.

To select which package might be not needed and just takes space hence you need to to list all installed packages on the system ordered by their size this is different in Debian based Linuces e.g. – Debian GNU / Linux / Ubuntu / Mint etc. and RPM based ones Fedora / CentOS / OpenSuSE

1. List all RPM installed packages by Size on CentOS / SuSE

Finding how much space each of the installed rpm packages take on the HDD and displaying them in a sorted order is done with:

rpm -qa –queryformat '%10{size} – %-25{name} \t %{version}\n' | sort -n

From the command above,  the '%10{size}' option aligns the size of the package to the right with a padding of 10 characters. The '%-25{name} aligns the name of the package to the left, padded to 25 characters. The '%{version} indicates the version and 'sort -n' flag sorts the packages according to size from the smallest to the largest in bytes.

2. List all installed RPM packages sorted by size on Fedora

Fedora has introduced the dnf package manager instead of yum, to get how much size individual rpm package occupies on system:

dnf info samba
Available Packages
Name        : samba
Arch        : x86_64
Epoch       : 2
Version     : 4.1.20
Release     : 1.fc21
Size        : 558 k
Repo        : updates
Summary     : Server and Client software to interoperate with Windows machines
URL         :
License     : GPLv3+ and LGPLv3+
Description : Samba is the standard Windows interoperability suite of programs
            : for Linux and Unix.

To get a list of all packages on system with their size

dnf info * | grep -i "Installed size" |sort -n

3. List all installed DEB packages on Debian / Ubuntu / Mint etc. with dpkg / aptitude / apt-get and wajig

The most simple way to get a list of largest packages is through dpkg

# dpkg-query -Wf '${Installed-Size}\t${Package}\n' | sort -n
6       default-jre
6       libpython-all-dev
6       libtinfo-dev
6       python-all
6       python-all-dev
6       task-cinnamon-desktop
6       task-cyrillic
6       task-desktop
6       task-english
6       task-gnome-desktop
6       task-laptop
6       task-lxde-desktop
6       task-mate-desktop
6       task-print-server
6       task-ssh-server
6       task-xfce-desktop
8       mysql-client
8       printer-driver-all

207766    libwine
215625    google-chrome-stable
221908    libwine
249401    frogatto-data
260717    linux-image-4.19.0-5-amd64
262512    linux-image-4.19.0-6-amd64
264899    mame
270589    fonts-noto-extra
278903    skypeforlinux
480126    metasploit-framework

above cmd displays packages in size order, largest package last, but the output will include also size of packages, that used to exist,
have been removed but was not purged. Thus if you find  a package that is shown as very large by size but further dpkg -l |grep -i package-name shows package as purged e.g. package state is not 'ii' but 'rc', the quickest work around is to purge all removed packages, that are still not purged and have some configuration remains and other chunks of data that just take space for nothing with:

# dpkg –list |grep "^rc" | cut -d " " -f 3 | xargs sudo dpkg –purge

Be cautious when you execute above command, because if for some reason you uninstalled a package with the idea to keep old configuration files only and in case if you decide to use it some time in future to reuse already custom made configs but do run above purge commands all such package saved kept configs will disappear.
For people who don't want to mess up with, uninstalled but present packages use this to filter out ready to be purged state packages.

# dpkg-query -Wf '${db:Status-Status} ${Installed-Size}\t${Package}\n' | sed -ne 's/^installed //p'|sort -n

aptitude – (high level ncurses interface like to package management) can also be easily used to list largest size packages eating up your hard drive in both interactive or cli mode, like so:

# aptitude search –sort '~installsize' –display-format '%p %I' '~i' | head
metasploit-framework 492 MB
skypeforlinux 286 MB
fonts-noto-extra 277 MB
mame 271 MB
linux-image-4.19.0-6-amd64 269 MB
linux-image-4.19.0-5-amd64 267 MB
frogatto-data 255 MB
libwine 227 MB
google-chrome-stable 221 MB
libwine:i386 213 MB

  • –sort is package sort order, and ~installsize specifies a package sort policy.
  • installsize means 'sort on (estimated) installed size', and the preceding ~ means sort descending (since default for all sort policies is ascending).
  • –display-format changes the <you guessed :->. The format string '%p %I' tells aptitude to output package name, then installed size.
  • '~i' tells aptitude to search only installed packages.

How much a certain .deb package removal will free up on the disk can be seen with apt-get as well to do so for the famous 3D acceleration Graphic Card (enabled) or not  test game extremetuxracer

apt-get –assume-no –purge remove "texlive*" | grep "be freed" | 
   awk '{print $4, $5}'

Perhaps,  the easiest to remember and more human readable output biggest packages occupied space on disk is to install and use a little proggie called wajig to do so

# apt install –yes wajig

Here is how to pick up 10 biggest size packages.

root@jeremiah:/home/hipo# wajig large|tail -n 10
fonts-noto-cjk-extra               204,486      installed
google-chrome-stable               215,625      installed
libwine                            221,908      installed
frogatto-data                      249,401      installed
linux-image-4.19.0-5-amd64         260,717      installed
linux-image-4.19.0-6-amd64         262,512      installed
mame                               264,899      installed
fonts-noto-extra                   270,589      installed
skypeforlinux                      278,903      installed
metasploit-framework               480,126      installed

As above example lists a short package name and no description for those who want get more in depth knowledge on what exactly is the package bundle used for use:

# aptitude search –sort '~installsize' –display-format '%30p %I %r %60d' '~i' |head

%30p %I %r %60d display more information in your format string, or change field widths, enhanced format string

Meaning of parameters is:

  • %30p : package name in field width=30 char
  • %I : estimated install size
  • %r : 'reverse depends count': approximate number of other installed packages which depend upon this package
  • %60d : package's short description in field width=60 char

wajig is capable is a python written and idea is to easify Debian console package management (so you don't have to all time remember when and with which arguments to use apt-get / apt-cache etc.), below is list of commands it accepts.

root@jeremiah:/home/hipo## wajig commands
addcdrom           Add a Debian CD/DVD to APT's list of available sources
addrepo            Add a Launchpad PPA (Personal Package Archive) repository
aptlog             Display APT log file
autoalts           Mark the Alternative to be auto-set (using set priorities)
autoclean          Remove no-longer-downloadable .deb files from the download cache
autodownload       Do an update followed by a download of all updated packages
autoremove         Remove unused dependency packages
build              Get source packages, unpack them, and build binary packages from them.
builddeps          Install build-dependencies for given packages
changelog          Display Debian changelog of a package
clean              Remove all deb files from the download cache
contents           List the contents of a package file (.deb)
dailyupgrade       Perform an update then a dist-upgrade
dependents         Display packages which have some form of dependency on the given package
describe           Display one-line descriptions for the given packages
describenew        Display one-line descriptions of newly-available packages
distupgrade        Comprehensive system upgrade
download           Download one or more packages without installing them
editsources        Edit list of Debian repository locations for packages
extract            Extract the files from a package file to a directory
fixconfigure       Fix an interrupted install
fixinstall         Fix an install interrupted by broken dependencies
fixmissing         Fix and install even though there are missing dependencies
force              Install packages and ignore file overwrites and depends
hold               Place packages on hold (so they will not be upgraded)
info               List the information contained in a package file
init               Initialise or reset wajig archive files
install            Package installer
installsuggested   Install a package and its Suggests dependencies
integrity          Check the integrity of installed packages (through checksums)
large              List size of all large (>10MB) installed packages
lastupdate         Identify when an update was last performed
listall            List one line descriptions for all packages
listalternatives   List the objects that can have alternatives configured
listcache          List the contents of the download cache
listcommands       Display all wajig commands
listdaemons        List the daemons that wajig can start, stop, restart, or reload
listfiles          List the files that are supplied by the named package
listhold           List packages that are on hold (i.e. those that won't be upgraded)
listinstalled      List installed packages
listlog            Display wajig log file
listnames          List all known packages; optionally filter the list with a pattern
listpackages       List the status, version, and description of installed packages
listscripts        List the control scripts of the package of deb file
listsection        List packages that belong to a specific section
listsections       List all available sections
liststatus         Same as list but only prints first two columns, not truncated
localupgrade       Upgrade using only packages that are already downloaded
madison            Runs the madison command of apt-cache
move               Move packages in the download cache to a local Debian mirror
new                Display newly-available packages
newdetail          Display detailed descriptions of newly-available packages
news               Display the NEWS file of a given package
nonfree            List packages that don't meet the Debian Free Software Guidelines
orphans            List libraries not required by any installed package 
policy             From preferences file show priorities/policy (available)
purge              Remove one or more packages and their configuration files
purgeorphans       Purge orphaned libraries (not required by installed packages)
purgeremoved       Purge all packages marked as deinstall
rbuilddeps         Display the packages which build-depend on the given package
readme             Display the README file(s) of a given package
recdownload        Download a package and all its dependencies
recommended        Display packages installed as Recommends and have no dependents
reconfigure        Reconfigure package
reinstall          Reinstall the given packages
reload             Reload system daemons (see LIST-DAEMONS for available daemons)
remove             Remove packages (see also PURGE command)
removeorphans      Remove orphaned libraries
repackage          Generate a .deb file from an installed package
reportbug          Report a bug in a package using Debian BTS (Bug Tracking System)
restart            Restart system daemons (see LIST-DAEMONS for available daemons)
rpm2deb            Convert an .rpm file to a Debian .deb file
rpminstall         Install an .rpm package file
search             Search for package names containing the given pattern
searchapt          Find nearby Debian package repositories
show               Provide a detailed description of package
sizes              Display installed sizes of given packages
snapshot           Generates a list of package=version for all installed packages
source             Retrieve and unpack sources for the named packages
start              Start system daemons (see LIST-DAEMONS for available daemons)
status             Show the version and available versions of packages
statusmatch        Show the version and available versions of matching packages
stop               Stop system daemons (see LISTDAEMONS for available daemons)
tasksel            Run the task selector to install groups of packages
todo               Display the TODO file of a given package
toupgrade          List versions of upgradable packages
tutorial           Display wajig tutorial
unhold             Remove listed packages from hold so they are again upgradeable
unofficial         Search for an unofficial Debian package at
update             Update the list of new and updated packages
updatealternatives Update default alternative for things like x-window-manager
updatepciids       Updates the local list of PCI ids from the internet master list
updateusbids       Updates the local list of USB ids from the internet master list
upgrade            Conservative system upgrade
upgradesecurity    Do a security upgrade
verify             Check package's md5sum
versions           List version and distribution of given packages
whichpackage       Search for files matching a given pattern within packages


4. List installed packages order by size in Arch Linux

ArchLinux is using the funny named package manager – pacman (a nice prank for the good old arcade game).
What is distinctive of pacman uses libalpm (Arch Linux Package Management (ALPM) library) as a back-end to perform all the actions.

# pacman -Qi | awk '/^Name/{name=$3} /^Installed Size/{print $4$5, name}' | sort -hr | head -25
296.64MiB linux-firmware
144.20MiB python
105.43MiB gcc-libs
72.90MiB python2
66.91MiB linux
57.47MiB perl
45.49MiB glibc
35.33MiB icu
34.68MiB git
30.96MiB binutils
29.95MiB grub
18.96MiB systemd
13.94MiB glib2
13.79MiB coreutils
13.41MiB python2-boto
10.65MiB util-linux
9.50MiB gnupg
8.09MiB groff
8.05MiB gettext
7.99MiB texinfo
7.93MiB sqlite
7.15MiB bash
6.50MiB lvm2
6.43MiB openssl
6.33MiB db

There is another mean to list packages by size using a ArchLinux tool called pacgraph

# pacgraph -c | head -25

Autodetected Arch.
Loading package info
Total size: 1221MB
367MB linux
144MB pacgraph
98MB cloud-init
37MB grub
35MB icu
34MB git
31698kB binutils
19337kB pacman
11029kB man-db
8186kB texinfo
8073kB lvm2
7632kB nano
7131kB openssh
5735kB man-pages
3815kB xfsprogs
3110kB sudo
3022kB wget
2676kB tar
2626kB netctl
1924kB parted
1300kB procps-ng
1248kB diffutils


4. Debian Goodies

Most debian users perhaps never hear of debian-goodies package, but I thought it is worthy to mention it as sooner or later as a sysadmin or .deb based Desktop user it might help you somewhere.

Debian-goodies is sall toolbox-style utilities for Debian systems
 These programs are designed to integrate with standard shell tools,
 extending them to operate on the Debian packaging system.

  dglob  – Generate a list of package names which match a pattern
           [dctrl-tools, apt*, apt-file*, perl*]
  dgrep  – Search all files in specified packages for a regex
           [dctrl-tools, apt-file (both via dglob)]
 These are also included, because they are useful and don't justify
 their own packages:
           – find packages which enhance installed packages [apt,
           – Help to find and restart processes which are using old versions
               of upgraded files (such as libraries) [python3, procps, lsof*]
  debget     – Fetch a .deb for a package in APT's database [apt]
  debman     – Easily view man pages from a binary .deb without extracting
               [man, apt* (via debget)]
  debmany    – Select manpages of installed or uninstalled packages [man |
               sensible-utils, whiptail | dialog | zenity, apt*, konqueror*,
               libgnome2-bin*, xdg-utils*]
  dhomepage  – Open homepage of a package in a web browser [dctrl-tools,
               sensible-utils*, www-browser* | x-www-browser*]
  dman       – Fetch manpages from online service [curl,
               man, lsb-release*]
  dpigs      – Show which installed packages occupy the most space
             – Get list of dbgsym packages from core dump or PID [dctrl-tools,
               elfutils, libfile-which-perl, libipc-system-simple-perl]
  popbugs    – Display a customized release-critical bug list based on
               packages you use (using popularity-contest data) [python3,
             – find which package might have broken another [python3, apt]
             – find which package might have broken the build of another
               [python3 (via which-pkg-broke), apt]

Even simpler by that is to use dpigs shell script part of the debian-goodies package which will automatically print out the largest packages.

dpigs command output is exactly the same as 'dpkg-query -Wf '${Installed-Size}\t${Package}\n' | sort -nr | head', but is useful cause you don't have to remember that complex syntax.

5. Checking where your space is gone in a Spacesniffer like GUI manner with Baobab

In my prior article Must have software on a new installed Windows 2 of the  of the precious tools to set are Spacesniffer and WinDirStat.
Windows users will be highly delighted to know that SpaceSniffer equivallent is already present on Linux – say hello baobab.
is simple but useful Graphic disk usage overview program for those who don't want to mess to much with the console / terminal to find out which might be the possible directory candidate for removal. It is very simplistic but it does well what it is aimed for, to install it on a Debian or .deb based OS.

# apt install –yes baobab


baobab Linux Hard Disk Usage Analyzer for GNOME. – It can easily scan either the whole filesystem or a specific user-requested branch (Iocal or remote)


Baobab / (root) directory statistics Rings Chart pie


baobab – Treemap Chart for directory usage sorted by size on disk 

!!! Note that before removing any files found as taking up too much space with baobab – make sure this files are not essential parts of a .deb package first, otherwise you might break up your system !!!

KDE (Plasma) QT library users could use Qdirstat instead of baobab 

qdirstat-on-gnu-linur checking what is the disk space bottleneck qdirstat KDE

6. Use ncdu or duper perl script tool to generate directory disk usage in ASCII chart bar

ncdu and duper are basicly the same except one is using ncurses and is interactive in a very simplistic interface with midnight commander.

# apt install –yes ncdu
# ncdu /root


# apt-get install –yes durep
# durep -td 1 /usr

[ /usr    14.4G (0 files, 11 dirs) ]
   6.6G [#############                 ]  45.54% lib/
   5.5G [###########                   ]  38.23% share/
   1.1G [##                            ]   7.94% bin/
 552.0M [#                             ]   3.74% local/
 269.2M [                              ]   1.83% games/
 210.4M [                              ]   1.43% src/
  88.9M [                              ]   0.60% libexec/
  51.3M [                              ]   0.35% sbin/
  41.2M [                              ]   0.28% include/
   8.3M [                              ]   0.06% lib32/
 193.8K [                              ]   0.00% lib64/



In this article, I've shortly explained the few approach you can take to handle low disk space preventing you to update a regular security updates on Linux.
The easiest one is to clone your drive to a bigger (larger) sized SATA HDD or SDD Drive or using a free space left on a hard drive to exnted the current filling up the root partition. 

Further, I looked through the common reasons for endind with a disk being low spaced and a quick work around to free disk space through listing and purging larges sized package, this is made differently in different Linux distributions, because different Linux has different package managers. As I'm primary using Debian, I explained thoroughfully on how this is achieved with apt-get / dpkg-query / dpkg / aptitude and the little known debian-goodies .deb package manager helper pack. For GUI Desktop users there is baobab / qdirstat. ASCII lovers could enjoy durep and ncdu.

That's all folks hope you enjoyed and learned something new. If you know of other cool tools or things this article is missing please share.

Export / Import PuTTY Tunnels SSH Sessions from one to another Windows machine howto

Thursday, January 31st, 2019


As I've started on job position – Linux Architect in last November 2018 in Itelligence AG as a contractor (External Service) – a great German company who hires the best IT specialists out there and offers a flexible time schedules for emploees doing various very cool IT advanced operations and Strategic advancement of SAP's Cloud used Technology and Services improvements for SAP SE – SAP S4HANA and HEC (HANA Enterprise Cloud) and been given for work hardware a shiny Lenovo Thinkpad 500 Laptop with Windows 10 OS (SAP pre-installed), I needed to make some SSH Tunnels to machines to (Hop Station / Jump hosts) for that purpose, after some experimenting with MobaXterm Free (Personal Edition 11.0) and the presumable limitations of tunnels of the free client as well as my laziness to add the multiple ssh tunnels to different ssh / rdp / vnc etc. servers, finally I decided to just copy all the tunnels from a colleague who runs Putty and again use the good old Putty – old school Winblows SSH Terminal Client but just for creating the SSH tunnels and for rest use MobaXterm, just like in old times while still employe in Hewlett Packard. For that reason to copy the Tunnels from my dear German Colleague Henry Beck (A good herated collegue who works in field of Storage dealing with NetApps / filer Clusters QNap etc.).

Till that moment I had no idea how copying a saved SSH Tunnels definition is possible, I did a quick research just to find out this is done not with Putty Interface itself but, insetead through dumping Windows Putty Stored Registry records into a File, then transfer to the PC where Tunnels needs to be imported and then again (either double click the registry file) to load it, into registry or use Windows registry editor command line interface reg, here is how:

1. Export


Run cmd.exe (note below command) 

requires elevated Run as Administrator prompt:

Only sessions:

regedit /e "%USERPROFILE%\Desktop\putty-sessions.reg" HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\Sessions

All settings:

regedit /e "%USERPROFILE%\Desktop\putty.reg" HKEY_CURRENT_USER\Software\SimonTatham


If you have powershell installed on machine, to dump

Only sessions:


reg export HKCU\Software\SimonTatham\PuTTY\Sessions ([Environment]::GetFolderPath("Desktop") + "\putty-sessions.reg")

All settings:

reg export HKCU\Software\SimonTatham ([Environment]::GetFolderPath("Desktop") + "\putty.reg")

2. Import

Double-click on the 


 file and accept the import.

Alternative ways:



require elevated command prompt:

regedit /i putty-sessions.reg regedit /i putty.reg


reg import putty-sessions.reg reg import putty.reg

Below are some things to consider:

Note !do not replace 


 with your username.

Note !: It will create a 


 file on the Desktop of the current user (for a different location modify path)

Note !: It will not export your related (old system stored) SSH keys.

What to expect next?


The result is in Putty you will have the Tunnel sessions loadable when you launch (Portable or installed) Putty version.
Press Load button over the required saved Tunnels list and there you go under

Connection SSH -> Tunnels 

you will see all the copied tunnels.


How to install KVM Kernel-based Virtual Machine Virtualization on Linux

Sunday, October 14th, 2018


If you want to run multiple virtual machines on GNU / Linux server or your Linux powered Desktop you have the possibility to use a couple of Virtual Machines just to name a few VirtualBox and VMWare are the option the native way to do it is using the Linux kernel via a loadable kernel module called KVM (Kernel-based Virtual Machine).
Though Oracle's Virtualbox generally works and you could add new test beds virtual machines (install multiple Linux / *BSD OS) it is not fully Free Software and not even fully open source licensed, VMWare even though superior as a Virtualization product is proprietary and its application costs a lot of money which not each develpoper or small / mid-sized company could afford.

Once the kvm.ko module is loaded your Linux kernel turns into a full-featured Virtual Machine Hypervisor.
Starting with Linux kernel 2.6.X the KVM Hypervisor is available and easy to install virtually all modern Linux distributions Redhat / CentOS Debian / Ubuntu etc. support it and its up to running few commands to install and start using the Power of Kernel embedded Virtualization.

KVM could be used to run in parallel multiple Operating Systems such as Windows / Linux / FreeBSD and others of BSDs family,  each running under a separate virtual machine with its private dedicated (isolated), disc, graphic card, network card etc.

To start up I assume you have already installed some kind of Linux distribution either locally or on a remote dedicated server.

1. Installing KVM on Debian GNU / Linux / Ubuntu / Mint and other deb based distros

Using APT tool install below packages:

root@jeremiah:~# apt install –yes qemu-kvm libvirt-clients libvirt-daemon-system bridge-utils libguestfs-tools genisoimage virtinst libosinfo-bin

2. Installing virt-manager GUI to manage Virtual servers

root@jeremiah:~# apt-cache show virt-manager|grep -i desc -A 1
Description-en: desktop application for managing virtual machines
 It presents a summary view of running domains and their live performance &

Description-md5: 9f7f584744b77cdacc2291f2a8ac220e

root@jeremiah:~# apt install –yes virt-manager



3. Configure bridged networking to allow access to newly configured VMs

Bridging has to be added via /etc/network/interfaces therefore it is a good idea to create a backup of it before modifying:

# cp -rpf /etc/network/interfaces /etc/network/interfaces.bakup-$(echo $(date '+%Y-%m-%d-%H'))

# vim /etc/network/interfaces

auto br0
 iface br0 inet static
         # set static route for LAN
      post-up route add -net netmask gw
      post-up route add -net netmask gw
         bridge_ports eth0
         bridge_stp off
         bridge_fd 0
         bridge_maxwait 0
 # br1 setup with static wan IPv4 with ISP router as a default gateway
 auto br1
 iface br1 inet static
         bridge_ports eth1
         bridge_stp off
         bridge_fd 0
         bridge_maxwait 0

Once file is saved in vim editor restart the networking.

# systemctl restart network.manager

To verify whether the bridge has been succesfully upped.

root@jeremiah:/home/hipo/kvm# brctl show
bridge name    bridge id        STP enabled    interfaces
virbr0        8000.525400cb1cd1    yes        virbr0-nic

4. List all installable Virtual OS images

root@jeremiah:/home/hipo/kvm# virt-builder -list
centos-6                 x86_64     CentOS 6.6
centos-7.0               x86_64     CentOS 7.0
centos-7.1               x86_64     CentOS 7.1
centos-7.2               aarch64    CentOS 7.2 (aarch64)
centos-7.2               x86_64     CentOS 7.2
centos-7.3               x86_64     CentOS 7.3
centos-7.4               x86_64     CentOS 7.4
centos-7.5               x86_64     CentOS 7.5
cirros-0.3.1             x86_64     CirrOS 0.3.1
cirros-0.3.5             x86_64     CirrOS 0.3.5
debian-6                 x86_64     Debian 6 (Squeeze)
debian-7                 sparc64    Debian 7 (Wheezy) (sparc64)
debian-7                 x86_64     Debian 7 (wheezy)
debian-8                 x86_64     Debian 8 (jessie)
debian-9                 x86_64     Debian 9 (stretch)
fedora-18                x86_64     Fedora® 18
fedora-19                x86_64     Fedora® 19
fedora-20                x86_64     Fedora® 20
fedora-21                aarch64    Fedora® 21 Server (aarch64)
fedora-21                armv7l     Fedora® 21 Server (armv7l)
fedora-21                ppc64      Fedora® 21 Server (ppc64)
fedora-21                ppc64le    Fedora® 21 Server (ppc64le)
fedora-21                x86_64     Fedora® 21 Server
fedora-22                aarch64    Fedora® 22 Server (aarch64)
fedora-22                armv7l     Fedora® 22 Server (armv7l)
fedora-22                i686       Fedora® 22 Server (i686)
fedora-22                x86_64     Fedora® 22 Server
fedora-23                aarch64    Fedora® 23 Server (aarch64)
fedora-23                armv7l     Fedora® 23 Server (armv7l)
fedora-23                i686       Fedora® 23 Server (i686)
fedora-23                ppc64      Fedora® 23 Server (ppc64)
fedora-23                ppc64le    Fedora® 23 Server (ppc64le)
fedora-23                x86_64     Fedora® 23 Server
fedora-24                aarch64    Fedora® 24 Server (aarch64)
fedora-24                armv7l     Fedora® 24 Server (armv7l)
fedora-24                i686       Fedora® 24 Server (i686)
fedora-24                x86_64     Fedora® 24 Server
fedora-25                aarch64    Fedora® 25 Server (aarch64)
fedora-25                armv7l     Fedora® 25 Server (armv7l)
fedora-25                i686       Fedora® 25 Server (i686)
fedora-25                ppc64      Fedora® 25 Server (ppc64)
fedora-25                ppc64le    Fedora® 25 Server (ppc64le)
fedora-25                x86_64     Fedora® 25 Server
fedora-26                aarch64    Fedora® 26 Server (aarch64)
fedora-26                armv7l     Fedora® 26 Server (armv7l)
fedora-26                i686       Fedora® 26 Server (i686)
fedora-26                ppc64      Fedora® 26 Server (ppc64)
fedora-26                ppc64le    Fedora® 26 Server (ppc64le)
fedora-26                x86_64     Fedora® 26 Server
fedora-27                aarch64    Fedora® 27 Server (aarch64)
fedora-27                armv7l     Fedora® 27 Server (armv7l)
fedora-27                i686       Fedora® 27 Server (i686)
fedora-27                ppc64      Fedora® 27 Server (ppc64)
fedora-27                ppc64le    Fedora® 27 Server (ppc64le)
fedora-27                x86_64     Fedora® 27 Server
fedora-28                i686       Fedora® 28 Server (i686)
fedora-28                x86_64     Fedora® 28 Server
freebsd-11.1             x86_64     FreeBSD 11.1
scientificlinux-6        x86_64     Scientific Linux 6.5
ubuntu-10.04             x86_64     Ubuntu 10.04 (Lucid)
ubuntu-12.04             x86_64     Ubuntu 12.04 (Precise)
ubuntu-14.04             x86_64     Ubuntu 14.04 (Trusty)
ubuntu-16.04             x86_64     Ubuntu 16.04 (Xenial)
ubuntu-18.04             x86_64     Ubuntu 18.04 (bionic)
opensuse-13.1            x86_64     openSUSE 13.1
opensuse-13.2            x86_64     openSUSE 13.2
opensuse-42.1            x86_64     openSUSE Leap 42.1
opensuse-tumbleweed      x86_64     openSUSE Tumbleweed

5. Create Virtual Machine OS-es from scratch with virt-builder

Below we'll create two images one for Fedora 28 and 1 for Debian 9 using the virt-builder (a tool to build virtual images quickly), the images that could be used are shown through below virt-builder –list command.

# iso='fedora-28';
# iso1='debian-9';

# sudo virt-builder $iso \
     –size=10G \
     –format qcow2 -o /var/lib/libvirt/images/$iso-vm1.qcow2 \
     –hostname $iso-vm1 \
     –network \
     –timezone Europe/Sofia

[   3.3] Downloading:
[   5.2] Planning how to build this image
[   5.2] Uncompressing
[  20.8] Resizing (using virt-resize) to expand the disk to 10.0G
[  50.8] Opening the new disk
[  53.7] Setting a random seed
[  53.7] Setting the hostname: fedora-28-vm1
[  53.7] Setting the timezone: Europe/Sofia
[  53.7] Setting passwords
virt-builder: Setting random password of root to YMTkxaJIkEU24Ytf

[  54.7] Finishing off
                   Output file: /var/lib/libvirt/images/fedora-28-vm1.qcow2
                   Output size: 10.0G
                 Output format: qcow2
            Total usable space: 9.3G
                    Free space: 8.2G (87%)

# sudo virt-builder $iso1 \
     –size=10G \
     –format qcow2 -o /var/lib/libvirt/images/$iso-vm1.qcow2 \
     –hostname $iso1-vm1 \
     –network \
     –timezone Europe/Sofia

[   3.2] Downloading:
[   4.1] Planning how to build this image
[   4.1] Uncompressing
[  16.9] Resizing (using virt-resize) to expand the disk to 10.0G
[  40.1] Opening the new disk
[  42.9] Setting a random seed
virt-builder: warning: random seed could not be set for this type of guest
[  42.9] Setting the hostname: debian-9-vm1
[  43.6] Setting the timezone: Europe/Sofia
[  43.6] Setting passwords
virt-builder: Setting random password of root to JtzEYGff9KxL5jCR
[  44.3] Finishing off
                   Output file: /var/lib/libvirt/images/debian-9-vm1.qcow2
                   Output size: 10.0G
                 Output format: qcow2
            Total usable space: 9.8G
                    Free space: 9.0G (91%)

vim bridged.xml

  <forward mode="bridge"/>
  <bridge name="br0"/>

# sudo virsh net-define –file bridged.xml
# sudo virsh net-autostart br0
# sudo virsh net-start br0

Above two commands will download pre-packaged KVM isos and store them inside /var/lib/libvirt/images/ you see also the root (administrator) password for both ISOs printed out.

root@jeremiah:/home/hipo/kvm# ls -ld /var/lib/libvirt/images/*
-rw-r–r– 1 root         root         10739318784 Oct 12 23:45 /var/lib/libvirt/images/debian-9-vm1.qcow2
-rw-r–r– 1 root         root         10739318784 Oct 12 23:46 /var/lib/libvirt/images/fedora-28-vm1.qcow2

To access directly the new created VMs as we have specified the –vnc option it is possible to directly vnc to the new host with VNC client (in linux I use vncviewer), on Windows you can use something like TightVNC.

6. Use official Linux distributions ISO boot files to install into KVM VM

Those who would like to run inside KVM VM Linux could do it directly using installable ISO files and install the set of Linux with the required packages, just like installing a fresh new Linux on a bare-metal machine.
To do so download your ISO image from the net (either from official distro website or a mirror website, in case if you need to spin an older version) and use virt-install to run the installer inside KVM.

root@jeremiah:~# cd /var/lib/libvirt/boot/;
root@jeremiah:~# wget

# sudo virt-install \
–virt-type=kvm \
–name centos7 \
–ram 2048 \
–vcpus=2 \
–os-variant=centos7.0 \
–virt-type=kvm \
–hvm \
–cdrom=/var/lib/libvirt/boot/CentOS-7-x86_64-DVD-1804.iso \
–network=bridge=br0,model=virtio \
–network=bridge=br1,model=virtio \
–graphics vnc \
–disk path=/var/lib/libvirt/images/centos7.qcow2,size=40,bus=virtio,format=qcow2

7. List newly created VMs with Virsh command

root@jeremiah:/home/hipo/kvm# virsh list –all
 Id    Name                           State
 3     fedora-28                      running
 –     debian9                        shut off

The –all parameter lists all available VMs ready to spin, if you want to check what are the VMs that are only running use instead:

root@jeremiah:/home/hipo/kvm# virsh list
 Id    Name                           State
 3     fedora-28                      running

8. Install Virtual Machine OS-es

Below lines will install 2 Virtual machines one Fedora 28 and Debian 9

virt-install –import –name $os \
    –ram 2048 \
    –vcpu 2 \
    –disk path=/var/lib/libvirt/images/$os-vm1.qcow2,format=qcow2 \
    –os-variant fedora-unknown \
    –network=bridge=br0,model=virtio \
    –noautoconsole \
  –hvm \
  –graphics vnc

virt-install –import –name $os     \
–ram 2048     \
–vcpu 2     \
–disk path=/var/lib/libvirt/images/$os-vm1.qcow2,format=qcow2     \
–os-variant debian9     –network=bridge=br0,model=virtio     \
–noautoconsole \
–hvm \
–graphics vnc

To deploy more just change the virtual machine type in os variable and modify the –os-variant variable to match the distribution name, to get the correct –os-variant variables that can be passed use osinfo-query below is output of the cmd:

root@jeremiah:/home/hipo/kvm# osinfo-query os
 Short ID             | Name                                               | Version  | ID                                      
 altlinux1.0          | Mandrake RE Spring 2001                            | 1.0      |        
 altlinux2.0          | ALT Linux 2.0                                      | 2.0      |        
 altlinux2.2          | ALT Linux 2.2                                      | 2.2      |        
 altlinux2.4          | ALT Linux 2.4                                      | 2.4      |        
 altlinux3.0          | ALT Linux 3.0                                      | 3.0      |        
 altlinux4.0          | ALT Linux 4.0                                      | 4.0      |        
 altlinux4.1          | ALT Linux 4.1                                      | 4.1      |        
 altlinux5.0          | ALT Linux 5.0                                      | 5.0      |        
 altlinux6.0          | ALT Linux 6.0                                      | 6.0      |        
 altlinux7.0          | ALT Linux 7.0                                      | 7.0      |        
 centos6.0            | CentOS 6.0                                         | 6.0      |            
 centos6.1            | CentOS 6.1                                         | 6.1      |            
 centos6.2            | CentOS 6.2                                         | 6.2      |            
 centos6.3            | CentOS 6.3                                         | 6.3      |            
 centos6.4            | CentOS 6.4                                         | 6.4      |            
 centos6.5            | CentOS 6.5                                         | 6.5      |            
 centos6.6            | CentOS 6.6                                         | 6.6      |            
 centos6.7            | CentOS 6.7                                         | 6.7      |            
 centos6.8            | CentOS 6.8                                         | 6.8      |            
 centos6.9            | CentOS 6.9                                         | 6.9      |            
 centos7.0            | CentOS 7.0                                         | 7.0      |            
 debian1.1            | Debian Buzz                                        | 1.1      |            
 debian1.2            | Debian Rex                                         | 1.2      |            
 debian1.3            | Debian Bo                                          | 1.3      |            
 debian2.0            | Debian Hamm                                        | 2.0      |            
 debian2.1            | Debian Slink                                       | 2.1      |            
 debian2.2            | Debian Potato                                      | 2.2      |            
 debian3              | Debian Woody                                       | 3        |              
 debian3.1            | Debian Sarge                                       | 3.1      |            
 debian4              | Debian Etch                                        | 4        |              
 debian5              | Debian Lenny                                       | 5        |              
 debian6              | Debian Squeeze                                     | 6        |              
 debian7              | Debian Wheezy                                      | 7        |              
 debian8              | Debian Jessie                                      | 8        |              
 debian9              | Debian Stretch                                     | 9        |              
 debiantesting        | Debian Testing                                     | testing  |        
 fedora-unknown       | Fedora                                             | unknown  |
 fedora1              | Fedora Core 1                                      | 1        |       
 fedora10             | Fedora 10                                          | 10       |      
 fedora11             | Fedora 11                                          | 11       |      
 fedora12             | Fedora 12                                          | 12       |      
 fedora13             | Fedora 13                                          | 13       |      
 fedora14             | Fedora 14                                          | 14       |      
 fedora15             | Fedora 15                                          | 15       |      
 fedora16             | Fedora 16                                          | 16       |      
 fedora17             | Fedora 17                                          | 17       |      
 fedora18             | Fedora 18                                          | 18       |      
 fedora19             | Fedora 19                                          | 19       |      
 fedora2              | Fedora Core 2                                      | 2        |       
 fedora20             | Fedora 20                                          | 20       |      
 fedora21             | Fedora 21                                          | 21       |      
 fedora22             | Fedora 22                                          | 22       |      
 fedora23             | Fedora 23                                          | 23       |      
 fedora24             | Fedora 24                                          | 24       |      
 fedora25             | Fedora 25                                          | 25       |      
 fedora26             | Fedora 26                                          | 26       |      
 fedora3              | Fedora Core 3                                      | 3        |       
 fedora4              | Fedora Core 4                                      | 4        |       
 fedora5              | Fedora Core 5                                      | 5        |       
 fedora6              | Fedora Core 6                                      | 6        |       
 fedora7              | Fedora 7                                           | 7        |       
 fedora8              | Fedora 8                                           | 8        |       
 fedora9              | Fedora 9                                           | 9        |       
 freebsd1.0           | FreeBSD 1.0                                        | 1.0      |          
 freebsd10.0          | FreeBSD 10.0                                       | 10.0     |         
 freebsd10.1          | FreeBSD 10.1                                       | 10.1     |         
 freebsd10.2          | FreeBSD 10.2                                       | 10.2     |         
 freebsd10.3          | FreeBSD 10.3                                       | 10.3     |         
 freebsd10.4          | FreeBSD 10.4                                       | 10.4     |         
 freebsd11.0          | FreeBSD 11.0                                       | 11.0     |         
 freebsd11.1          | FreeBSD 11.1                                       | 11.1     |         
 freebsd2.0           | FreeBSD 2.0                                        | 2.0      |          
 freebsd2.0.5         | FreeBSD 2.0.5                                      | 2.0.5    |        
 freebsd2.2.8         | FreeBSD 2.2.8                                      | 2.2.8    |        
 freebsd2.2.9         | FreeBSD 2.2.9                                      | 2.2.9    |        
 freebsd3.0           | FreeBSD 3.0                                        | 3.0      |          
 freebsd3.2           | FreeBSD 3.2                                        | 3.2      |          
 freebsd4.0           | FreeBSD 4.0                                        | 4.0      |          
 freebsd4.1           | FreeBSD 4.1                                        | 4.1      |          
 freebsd4.10          | FreeBSD 4.10                                       | 4.10     |         
 freebsd4.11          | FreeBSD 4.11                                       | 4.11     |         
 freebsd4.2           | FreeBSD 4.2                                        | 4.2      |          
 freebsd4.3           | FreeBSD 4.3                                        | 4.3      |          
 freebsd4.4           | FreeBSD 4.4                                        | 4.4      |          
 freebsd4.5           | FreeBSD 4.5                                        | 4.5      |          
 freebsd4.6           | FreeBSD 4.6                                        | 4.6      |          
 freebsd4.7           | FreeBSD 4.7                                        | 4.7      |          
 freebsd4.8           | FreeBSD 4.8                                        | 4.8      |          
 freebsd4.9           | FreeBSD 4.9                                        | 4.9      |          
 freebsd5.0           | FreeBSD 5.0                                        | 5.0      |          
 freebsd5.1           | FreeBSD 5.1                                        | 5.1      |          
 freebsd5.2           | FreeBSD 5.2                                        | 5.2      |          
 freebsd5.2.1         | FreeBSD 5.2.1                                      | 5.2.1    |        
 freebsd5.3           | FreeBSD 5.3                                        | 5.3      |          
 freebsd5.4           | FreeBSD 5.4                                        | 5.4      |          
 freebsd5.5           | FreeBSD 5.5                                        | 5.5      |          
 freebsd6.0           | FreeBSD 6.0                                        | 6.0      |          
 freebsd6.1           | FreeBSD 6.1                                        | 6.1      |          
 freebsd6.2           | FreeBSD 6.2                                        | 6.2      |          
 freebsd6.3           | FreeBSD 6.3                                        | 6.3      |          
 freebsd6.4           | FreeBSD 6.4                                        | 6.4      |          
 freebsd7.0           | FreeBSD 7.0                                        | 7.0      |          
 freebsd7.1           | FreeBSD 7.1                                        | 7.1      |          
 freebsd7.2           | FreeBSD 7.2                                        | 7.2      |          
 freebsd7.3           | FreeBSD 7.3                                        | 7.3      |          
 freebsd7.4           | FreeBSD 7.4                                        | 7.4      |          
 freebsd8.0           | FreeBSD 8.0                                        | 8.0      |          
 freebsd8.1           | FreeBSD 8.1                                        | 8.1      |          
 freebsd8.2           | FreeBSD 8.2                                        | 8.2      |          
 freebsd8.3           | FreeBSD 8.3                                        | 8.3      |          
 freebsd8.4           | FreeBSD 8.4                                        | 8.4      |          
 freebsd9.0           | FreeBSD 9.0                                        | 9.0      |          
 freebsd9.1           | FreeBSD 9.1                                        | 9.1      |          
 freebsd9.2           | FreeBSD 9.2                                        | 9.2      |          
 freebsd9.3           | FreeBSD 9.3                                        | 9.3      |          
 freedos1.2           | FreeDOS 1.2                                        | 1.2      |          
 gnome-continuous-3.10 | GNOME 3.10                                         | 3.10     |  
 gnome-continuous-3.12 | GNOME 3.12                                         | 3.12     |  
 gnome-continuous-3.14 | GNOME 3.14                                         | 3.14     |  
 gnome3.6             | GNOME 3.6                                          | 3.6      |              
 gnome3.8             | GNOME 3.8                                          | 3.8      |              
 macosx10.0           | MacOS X Cheetah                                    | 10.0     |            
 macosx10.1           | MacOS X Puma                                       | 10.1     |            
 macosx10.2           | MacOS X Jaguar                                     | 10.2     |            
 macosx10.3           | MacOS X Panther                                    | 10.3     |            
 macosx10.4           | MacOS X Tiger                                      | 10.4     |            
 macosx10.5           | MacOS X Leopard                                    | 10.5     |            
 macosx10.6           | MacOS X Snow Leopard                               | 10.6     |            
 macosx10.7           | MacOS X Lion                                       | 10.7     |            
 mageia1              | Mageia 1                                           | 1        |              
 mageia2              | Mageia 2                                           | 2        |              
 mageia3              | Mageia 3                                           | 3        |              
 mageia4              | Mageia 4                                           | 4        |              
 mageia5              | Mageia 5                                           | 5        |              
 mageia6              | Mageia 6                                           | 6        |              
 mandrake10.0         | Mandrake Linux 10.0                                | 10.0     |       
 mandrake10.1         | Mandrake Linux 10.1                                | 10.1     |       
 mandrake10.2         | Mandrake Linux 10.2                                | 10.2     |       
 mandrake5.1          | Mandrake Linux 5.1                                 | 5.1      |        
 mandrake5.2          | Mandrake Linux 5.2                                 | 5.2      |        
 mandrake5.3          | Mandrake Linux 5.3                                 | 5.3      |        
 mandrake6.0          | Mandrake Linux 6.0                                 | 6.0      |        
 mandrake6.1          | Mandrake Linux 6.1                                 | 6.1      |        
 mandrake7.0          | Mandrake Linux 7.0                                 | 7.0      |        
 mandrake7.1          | Mandrake Linux 7.1                                 | 7.1      |        
 mandrake7.2          | Mandrake Linux 7.2                                 | 7.2      |        
 mandrake8.0          | Mandrake Linux 8.0                                 | 8.0      |        
 mandrake8.1          | Mandrake Linux 8.1                                 | 8.1      |        
 mandrake8.2          | Mandrake Linux 8.2                                 | 8.2      |        
 mandrake9.0          | Mandrake Linux 9.0                                 | 9.0      |        
 mandrake9.1          | Mandrake Linux 9.1                                 | 9.1      |        
 mandrake9.2          | Mandrake Linux 9.2                                 | 9.2      |        
 mandriva2006.0       | Mandriva Linux 2006.0                              | 2006.0   |     
 mandriva2007         | Mandriva Linux 2007                                | 2007     |       
 mandriva2007.1       | Mandriva Linux 2007 Spring                         | 2007.1   |     
 mandriva2008.0       | Mandriva Linux 2008                                | 2008.0   |     
 mandriva2008.1       | Mandriva Linux 2008 Spring                         | 2008.1   |     
 mandriva2009.0       | Mandriva Linux 2009                                | 2009.0   |     
 mandriva2009.1       | Mandriva Linux 2009 Spring                         | 2009.1   |     
 mandriva2010.0       | Mandriva Linux 2010                                | 2010.0   |     
 mandriva2010.1       | Mandriva Linux 2010 Spring                         | 2010.1   |     
 mandriva2010.2       | Mandriva Linux 2010.2                              | 2010.2   |     
 mandriva2011         | Mandriva Linux 2011                                | 2011     |       
 mbs1.0               | Mandriva Business Server 1.0                       | 1.0      |             
 mes5                 | Mandriva Enterprise Server 5.0                     | 5.0      |             
 mes5.1               | Mandriva Enterprise Server 5.1                     | 5.1      |             
 msdos6.22            | Microsoft MS-DOS 6.22                              | 6.22     |         
 netbsd0.8            | NetBSD 0.8                                         | 0.8      |            
 netbsd0.9            | NetBSD 0.9                                         | 0.9      |            
 netbsd1.0            | NetBSD 1.0                                         | 1.0      |            
 netbsd1.1            | NetBSD 1.1                                         | 1.1      |            
 netbsd1.2            | NetBSD 1.2                                         | 1.2      |            
 netbsd1.3            | NetBSD 1.3                                         | 1.3      |            
 netbsd1.4            | NetBSD 1.4                                         | 1.4      |            
 netbsd1.5            | NetBSD 1.5                                         | 1.5      |            
 netbsd1.6            | NetBSD 1.6                                         | 1.6      |            
 netbsd2.0            | NetBSD 2.0                                         | 2.0      |            
 netbsd3.0            | NetBSD 3.0                                         | 3.0      |            
 netbsd4.0            | NetBSD 4.0                                         | 4.0      |            
 netbsd5.0            | NetBSD 5.0                                         | 5.0      |            
 netbsd5.1            | NetBSD 5.1                                         | 5.1      |            
 netbsd6.0            | NetBSD 6.0                                         | 6.0      |            
 netbsd6.1            | NetBSD 6.1                                         | 6.1      |            
 netbsd7.0            | NetBSD 7.0                                         | 7.0      |            
 netbsd7.1            | NetBSD 7.1                                         | 7.1      |            
 netbsd7.1.1          | NetBSD 7.1.1                                       | 7.1.1    |          
 netware4             | Novell Netware 4                                   | 4        |             
 netware5             | Novell Netware 5                                   | 5        |             
 netware6             | Novell Netware 6                                   | 6        |             
 openbsd4.2           | OpenBSD 4.2                                        | 4.2      |          
 openbsd4.3           | OpenBSD 4.3                                        | 4.3      |          
 openbsd4.4           | OpenBSD 4.4                                        | 4.4      |          
 openbsd4.5           | OpenBSD 4.5                                        | 4.5      |          
 openbsd4.8           | OpenBSD 4.8                                        | 4.8      |          
 openbsd4.9           | OpenBSD 4.9                                        | 4.9      |          
 openbsd5.0           | OpenBSD 5.0                                        | 5.0      |          
 openbsd5.1           | OpenBSD 5.1                                        | 5.1      |          
 openbsd5.2           | OpenBSD 5.2                                        | 5.2      |          
 openbsd5.3           | OpenBSD 5.3                                        | 5.3      |          
 openbsd5.4           | OpenBSD 5.4                                        | 5.4      |          
 openbsd5.5           | OpenBSD 5.5                                        | 5.5      |          
 openbsd5.6           | OpenBSD 5.6                                        | 5.6      |          
 openbsd5.7           | OpenBSD 5.7                                        | 5.7      |          
 openbsd5.8           | OpenBSD 5.8                                        | 5.8      |          
 openbsd5.9           | OpenBSD 5.9                                        | 5.9      |          
 openbsd6.0           | OpenBSD 6.0                                        | 6.0      |          
 openbsd6.1           | OpenBSD 6.1                                        | 6.1      |          
 openbsd6.2           | OpenBSD 6.2                                        | 6.2      |          
 opensolaris2009.06   | OpenSolaris 2009.06                                | 2009.06  |      
 opensuse-factory     | openSUSE                                           | factory  |    
 opensuse-unknown     | openSUSE                                           | unknown  |    
 opensuse10.2         | openSUSE 10.2                                      | 10.2     |       
 opensuse10.3         | openSUSE 10.3                                      | 10.3     |       
 opensuse11.0         | openSUSE 11.0                                      | 11.0     |       
 opensuse11.1         | openSUSE 11.1                                      | 11.1     |       
 opensuse11.2         | openSUSE 11.2                                      | 11.2     |       
 opensuse11.3         | openSUSE 11.3                                      | 11.3     |       
 opensuse11.4         | openSUSE 11.4                                      | 11.4     |       
 opensuse12.1         | openSUSE 12.1                                      | 12.1     |       
 opensuse12.2         | openSUSE 12.2                                      | 12.2     |       
 opensuse12.3         | openSUSE 12.3                                      | 12.3     |       
 opensuse13.1         | openSUSE 13.1                                      | 13.1     |       
 opensuse13.2         | openSUSE 13.2                                      | 13.2     |       
 opensuse42.1         | openSUSE Leap 42.1                                 | 42.1     |       
 opensuse42.2         | openSUSE Leap 42.2                                 | 42.2     |       
 opensuse42.3         | openSUSE Leap 42.3                                 | 42.3     |       
 opensusetumbleweed   | openSUSE Tumbleweed                                | tumbleweed |
 rhel-atomic-7.0      | Red Hat Enterprise Linux Atomic Host 7.0           | 7.0      |       
 rhel-atomic-7.1      | Red Hat Enterprise Linux Atomic Host 7.1           | 7.1      |       
 rhel-atomic-7.2      | Red Hat Enterprise Linux Atomic Host 7.2           | 7.2      |       
 rhel2.1              | Red Hat Enterprise Linux 2.1                       | 2.1      |              
 rhel2.1.1            | Red Hat Enterprise Linux 2.1 Update 1  
/etc/bind/masters/            | 2.1.1    |            
 rhel2.1.2            | Red Hat Enterprise Linux 2.1 Update 2              | 2.1.2    |            
 rhel2.1.3            | Red Hat Enterprise Linux 2.1 Update 3              | 2.1.3    |            
 rhel2.1.4            | Red Hat Enterprise Linux 2.1 Update 4              | 2.1.4    |            
 rhel2.1.5            | Red Hat Enterprise Linux 2.1 Update 5              | 2.1.5    |            
 rhel2.1.6            | Red Hat Enterprise Linux 2.1 Update 6              | 2.1.6    |            
 rhel2.1.7            | Red Hat Enterprise Linux 2.1 Update 7              | 2.1.7    |            
 rhel3                | Red Hat Enterprise Linux 3                         | 3        |                
 rhel3.1              | Red Hat Enterprise Linux 3 Update 1                | 3.1      |              
 rhel3.2              | Red Hat Enterprise Linux 3 Update 2                | 3.2      |              
 rhel3.3              | Red Hat Enterprise Linux 3 Update 3                | 3.3      |              
 rhel3.4              | Red Hat Enterprise Linux 3 Update 4                | 3.4      |              
 rhel3.5              | Red Hat Enterprise Linux 3 Update 5                | 3.5      |              
 rhel3.6              | Red Hat Enterprise Linux 3 Update 6                | 3.6      |              
 rhel3.7              | Red Hat Enterprise Linux 3 Update 7                | 3.7      |              
 rhel3.8              | Red Hat Enterprise Linux 3 Update 8                | 3.8      |              
 rhel3.9              | Red Hat Enterprise Linux 3 Update 9                | 3.9      |              
 rhel4.0              | Red Hat Enterprise Linux 4.0                       | 4.0      |              
 rhel4.1              | Red Hat Enterprise Linux 4.1                       | 4.1      |              
 rhel4.2              | Red Hat Enterprise Linux 4.2                       | 4.2      |              
 rhel4.3              | Red Hat Enterprise Linux 4.3                       | 4.3      |              
 rhel4.4              | Red Hat Enterprise Linux 4.4                       | 4.4      |              
 rhel4.5              | Red Hat Enterprise Linux 4.5                       | 4.5      |              
 rhel4.6              | Red Hat Enterprise Linux 4.6                       | 4.6      |              
 rhel4.7              | Red Hat Enterprise Linux 4.7                       | 4.7      |              
 rhel4.8              | Red Hat Enterprise Linux 4.8                       | 4.8      |              
 rhel4.9              | Red Hat Enterprise Linux 4.9                       | 4.9      |              
 rhel5.0              | Red Hat Enterprise Linux 5.0                       | 5.0      |              
 rhel5.1              | Red Hat Enterprise Linux 5.1                       | 5.1      |              
 rhel5.10             | Red Hat Enterprise Linux 5.10                      | 5.10     |             
 rhel5.11             | Red Hat Enterprise Linux 5.11                      | 5.11     |             
 rhel5.2              | Red Hat Enterprise Linux 5.2                       | 5.2      |              
 rhel5.3              | Red Hat Enterprise Linux 5.3                       | 5.3      |              
 rhel5.4              | Red Hat Enterprise Linux 5.4                       | 5.4      |              
 rhel5.5              | Red Hat Enterprise Linux 5.5                       | 5.5      |              
 rhel5.6              | Red Hat Enterprise Linux 5.6                       | 5.6      |              
 rhel5.7              | Red Hat Enterprise Linux 5.7                       | 5.7      |              
 rhel5.8              | Red Hat Enterprise Linux 5.8                       | 5.8      |              
 rhel5.9              | Red Hat Enterprise Linux 5.9                       | 5.9      |              
 rhel6.0              | Red Hat Enterprise Linux 6.0                       | 6.0      |              
 rhel6.1              | Red Hat Enterprise Linux 6.1                       | 6.1      |              
 rhel6.2              | Red Hat Enterprise Linux 6.2                       | 6.2      |              
 rhel6.3              | Red Hat Enterprise Linux 6.3                       | 6.3      |              
 rhel6.4              | Red Hat Enterprise Linux 6.4                       | 6.4      |              
 rhel6.5              | Red Hat Enterprise Linux 6.5                       | 6.5      |              
 rhel6.6              | Red Hat Enterprise Linux 6.6                       | 6.6      |              
 rhel6.7              | Red Hat Enterprise Linux 6.7                       | 6.7      |              
 rhel6.8              | Red Hat Enterprise Linux 6.8                       | 6.8      |              
 rhel6.9              | Red Hat Enterprise Linux 6.9                       | 6.9      |              
 rhel7.0              | Red Hat Enterprise Linux 7.0                       | 7.0      |              
 rhel7.1              | Red Hat Enterprise Linux 7.1                       | 7.1      |              
 rhel7.2              | Red Hat Enterprise Linux 7.2                       | 7.2      |              
 rhel7.3              | Red Hat Enterprise Linux 7.3                       | 7.3      |              
 rhel7.4              | Red Hat Enterprise Linux 7.4                       | 7.4      |              
 rhl1.0               | Red Hat Linux 1.0                                  | 1.0      |               
 rhl1.1               | Red Hat Linux 1.1                                  | 1.1      |               
 rhl2.0               | Red Hat Linux 2.0                                  | 2.0      |               
 rhl2.1               | Red Hat Linux 2.1                                  | 2.1      |               
 rhl3.0.3             | Red Hat Linux 3.0.3                                | 3.0.3    |             
 rhl4.0               | Red Hat Linux 4.0                                  | 4.0      |               
 rhl4.1               | Red Hat Linux 4.1                                  | 4.1      |               
 rhl4.2               | Red Hat Linux 4.2                                  | 4.2      |               
 rhl5.0               | Red Hat Linux 5.0                                  | 5.0      |               
 rhl5.1               | Red Hat Linux 5.1                                  | 5.1      |               
 rhl5.2               | Red Hat Linux 5.2                                  | 5.2      |               
 rhl6.0               | Red Hat Linux 6.0                                  | 6.0      |               
 rhl6.1               | Red Hat Linux 6.1                                  | 6.1      |               
 rhl6.2               | Red Hat Linux 6.2                                  | 6.2      |               
 rhl7                 | Red Hat Linux 7                                    | 7        |                 
 rhl7.1               | Red Hat Linux 7.1                                  | 7.1      |               
 rhl7.2               | Red Hat Linux 7.2                                  | 7.2      |               
 rhl7.3               | Red Hat Linux 7.3                                  | 7.3      |               
 rhl8.0               | Red Hat Linux 8.0                                  | 8.0      |               
 rhl9                 | Red Hat Linux 9                                    | 9        |                 
 sled10               | SUSE Linux Enterprise Desktop 10                   | 10       |                 
 sled10sp1            | SUSE Linux Enterprise Desktop 10 SP1               | 10.1     |               
 sled10sp2            | SUSE Linux Enterprise Desktop 10 SP2               | 10.2     |               
 sled10sp3            | SUSE Linux Enterprise Desktop 10 SP3               | 10.3     |               
 sled10sp4            | SUSE Linux Enterprise Desktop 10 SP4               | 10.4     |               
 sled11               | SUSE Linux Enterprise Desktop 11                   | 11       |                 
 sled11sp1            | SUSE Linux Enterprise Desktop 11 SP1               | 11.1     |               
 sled11sp2            | SUSE Linux Enterprise Desktop 11 SP2               | 11.2     |               
 sled11sp3            | SUSE Linux Enterprise Desktop 11 SP3               | 11.3     |               
 sled11sp4            | SUSE Linux Enterprise Desktop 11 SP4               | 11.4     |               
 sled12               | SUSE Linux Enterprise Desktop 12                   | 12       |                 
 sled12sp1            | SUSE Linux Enterprise Desktop 12 SP1               | 12.1     |               
 sled12sp2            | SUSE Linux Enterprise Desktop 12 SP2               | 12.2     |               
 sled9                | SUSE Linux Enterprise Desktop 9                    | 9        |                  
 sles10               | SUSE Linux Enterprise Server 10            
/etc/bind/masters/        | 10       |                 
 sles10sp1            | SUSE Linux Enterprise Server 10 SP1                | 10.1     |               
 sles10sp2            | SUSE Linux Enterprise Server 10 SP2                | 10.2     |               
 sles10sp3            | SUSE Linux Enterprise Server 10 SP3                | 10.3     |               
 sles10sp4            | SUSE Linux Enterprise Server 10 SP4                | 10.4     |               
 sles11               | SUSE Linux Enterprise Server 11                    | 11       |                 
 sles11sp1            | SUSE Linux Enterprise Server 11 SP1                | 11.1     |               
 sles11sp2            | SUSE Linux Enterprise Server 11 SP2                | 11.2     |               
 sles11sp3            | SUSE Linux Enterprise Server 11 SP3                | 11.3     |               
 sles11sp4            | SUSE Linux Enterprise Server 11 SP4                | 11.4     |               
 sles12               | SUSE Linux Enterprise Server 12                    | 12       |                 
 sles12sp1            | SUSE Linux Enterprise Server 12 SP1                | 12.1     |               
 sles12sp2            | SUSE Linux Enterprise Server 12 SP2                | 12.2     |               
 sles9                | SUSE Linux Enterprise Server 9                     | 9        |                  
 solaris10            | Solaris 10                                         | 10       |               
 solaris11            | Oracle Solaris 11                                  | 11       |            
 solaris9             | Solaris 9                                          | 9        |                
 ubuntu10.04          | Ubuntu 10.04 LTS                                   | 10.04    |          
 ubuntu10.10          | Ubuntu 10.10                                       | 10.10    |          
 ubuntu11.04          | Ubuntu 11.04                                       | 11.04    |          
 ubuntu11.10          | Ubuntu 11.10                                       | 11.10    |          
 ubuntu12.04          | Ubuntu 12.04 LTS                                   | 12.04    |          
 ubuntu12.10          | Ubuntu 12.10                                       | 12.10    |          
 ubuntu13.04          | Ubuntu 13.04                                       | 13.04    |          
 ubuntu13.10          | Ubuntu 13.10                                       | 13.10    |          
 ubuntu14.04          | Ubuntu 14.04 LTS                                   | 14.04    |          
 ubuntu14.10          | Ubuntu 14.10                                       | 14.10    |          
 ubuntu15.04          | Ubuntu 15.04                                       | 15.04    |          
 ubuntu15.10          | Ubuntu 15.10                                       | 15.10    |          
 ubuntu16.04          | Ubuntu 16.04                                       | 16.04    |          
 ubuntu16.10          | Ubuntu 16.10                                       | 16.10    |          
 ubuntu17.04          | Ubuntu 17.04                                       | 17.04    |          
 ubuntu17.10          | Ubuntu 17.10                                       | 17.10    |          
 ubuntu4.10           | Ubuntu 4.10                                        | 4.10     |           
 ubuntu5.04           | Ubuntu 5.04                                        | 5.04     |           
 ubuntu5.10           | Ubuntu 5.10                                        | 5.10     |           
 ubuntu6.06           | Ubuntu 6.06 LTS                                    | 6.06     |           
 ubuntu6.10           | Ubuntu 6.10                                        | 6.10     |           
 ubuntu7.04           | Ubuntu 7.04                                        | 7.04     |           
 ubuntu7.10           | Ubuntu 7.10                                        | 7.10     |           
 ubuntu8.04           | Ubuntu 8.04 LTS                                    | 8.04     |           
 ubuntu8.10           | Ubuntu 8.10                                        | 8.10     |           
 ubuntu9.04           | Ubuntu 9.04                                        | 9.04     |           
 ubuntu9.10           | Ubuntu 9.10                                        | 9.10     |           
 win1.0               | Microsoft Windows 1.0                              | 1.0      |            
 win10                | Microsoft Windows 10                               | 10.0     |             
 win2.0               | Microsoft Windows 2.0                              | 2.0      |            
 win2.1               | Microsoft Windows 2.1                              | 2.1      |            
 win2k                | Microsoft Windows 2000                             | 5.0      |             
 win2k12              | Microsoft Windows Server 2012                      | 6.3      |           
 win2k12r2            | Microsoft Windows Server 2012 R2                   | 6.3      |         
 win2k3               | Microsoft Windows Server 2003                      | 5.2      |            
 win2k3r2             | Microsoft Windows Server 2003 R2                   | 5.2      |          
 win2k8               | Microsoft Windows Server 2008                      | 6.0      |            
 win2k8r2             | Microsoft Windows Server 2008 R2                   | 6.1      |          
 win3.1               | Microsoft Windows 3.1                              | 3.1      |            
 win7                 | Microsoft Windows 7                                | 6.1      |              
 win8                 | Microsoft Windows 8                                | 6.2      |              
 win8.1               | Microsoft Windows 8.1                              | 6.3      |            
 win95                | Microsoft Windows 95                               | 4.0      |             
 win98                | Microsoft Windows 98                               | 4.1      |             
 winme                | Microsoft Windows Millennium Edition               | 4.9      |             
 winnt3.1             | Microsoft Windows NT Server 3.1                    | 3.1      |          
 winnt3.5             | Microsoft Windows NT Server 3.5                    | 3.5      |          
 winnt3.51            | Microsoft Windows NT Server 3.51                   | 3.51     |         
 winnt4.0             | Microsoft Windows NT Server 4.0                    | 4.0      |          
 winvista             | Microsoft Windows Vista                            | 6.0      |          
 winxp                | Microsoft Windows XP                               | 5.1      |  

9. Start / Stop listed KVM Virtual Machine

root@jeremiah:~# virsh list –all
 Id    Name                           State
 3     fedora-28                      running
 –     debian9                        shut off

To start debian9 linux virtual machine that is currently off

root@jeremiah:~# virsh start fedora-28
Domain fedora-28 started

root@jeremiah:/home/hipo# virsh start debian9
error: Failed to start domain debian9
error: Requested operation is not valid: network 'default' is not active

root@jeremiah:/home/hipo# virsh net-list –all
Name                 State      Autostart     Persistent
br0                  active     yes           yes
default              inactive   no            yes

root@jeremiah:/home/hipo# virsh net-start default
Network default started

root@jeremiah:/home/hipo# virsh start debian9
Domain debian9 started

10. Attach to running VM with virsh or virt-manager

root@jeremiah:~# virsh list
 Id    Name                           State
 1     fedora-28                      running
 3     debian9                        running

root@jeremiah:~# virsh connect debian9

Note that to make the login prompt appear you have to press enter once after the ^] connection string appears


An alternative way is to use virt-manager GUI KVM desktop management interface and click over the Virtual Machine Guest name, in same fashion like in VirtualBox.



If you have KVM running on your Linux desktop PC / notebook you can also connect via VNC with virsh command.

root@jericho:~# virsh vncdisplay centos7

Another handy thing is to expose the Virtualized Guest OS with VNC in order to be able to connect and manage installation or further Linux configuration via VNC using an SSH Tunnel with port forwarding:

$ ssh -L 5901:


11.  Start / Shutdown / Suspend / Reboot (safe reboot) a VM guest machine domain

root@jericho:~# virsh shutdown debian9
root@jericho:~# virsh start fedora-28
root@jericho:~# virsh suspend debian9
root@jericho:~# virsh reboot fedora-28

12. Remove / Delete KVM Virtual Machines domain

root@jeremiah:~# virsh undefine fedora-28
root@jeremiah:~# virsh destroy fedora-28

Closing words

Using KVM to experiment with different OS distributions is really fun just like you can easily run a number of the major most popular Linux Distributions and a set of different versions. It takes few minutes to have a fully functional Linux to play with and it saves a lot of hassles when dealing with GNU / Linux and FreeBSD, doing so in Virtualbox for me prooved to be much more complicated (not to mention that often Virtualbox had an ugly bugs so even Importing an Appliance as a Guest VM with an official distro OS-es failed with weird errors.
One other very practical use of Kerkel-based Virtualization is if you want to run your servers using own Micro-Services architecture (e.g. run multiple Linux OS-es each running a separate Apache / Nginx / MySQL / PostGreSQL / Backup / Storage) etc. all of it running on a single dedicated server or a self-hosted bare-metal
There are plenty of Web Interfaces for Management KVM (proprietary and free software) that could even futher simplify the use and deploy / destory of KVM VMs.
All that makes possible running your own Linux or Web hosting provider a relatively easy task and seriously could cut business expenses and operational (maintenance) costs.

If you plan to run youw own hosting company, I can help you establish your infrastructure and advise you on the right technologies to use.

Email Linux alternative text console clients to Thunderbird, fetchmail, Mutt, fetchmail + Alpine how to

Saturday, November 4th, 2017


As a GNU / Linux user you might end up searching for the best email client to satisfy your needs, for those who used so far Outlook Express on M$ Windows first switch to GNU / Linux the most likely one to choose is either Mozilla Thunderbird or GNOME's Evolution default Mail Clientbut what more text / console programs are there that will allow you to easily check email via POP3 and IMAP on Linux?

1. Install Fetchmail and use to collect and copy your emails from remote server to your local machine

 SSL enabled POP3, APOP, IMAP mail gatherer/forwarder
 fetchmail is a free, full-featured, robust, and well-documented remote mail
 retrieval and forwarding utility intended to be used over on-demand TCP/IP
 links (such as SLIP or PPP connections).  It retrieves mail from remote mail
 servers and forwards it to your local (client) machine's delivery system, so
 it can then be read by normal mail user agents such as mutt, elm, pine,
 (x)emacs/gnus, or mailx.  The fetchmailconf package includes an interactive
 GUI configurator suitable for end-users.

To install it, issue:

apt-get install –yes fetchmail procmail

To configure fetchmail to gather your mail from your POP3 / IMAP mailbox, create below
.fetchmailrc configuratoin and modify according to your account

# vim .fetchmailrc

#### .fetchmailrc
 set daemon 600
 set logfile fetchmail.log

 poll the_mail_server_hostname proto POP3

  user "Remote_Username" pass "PASSWORD=" is "local_username" preconnect "date >> fetchmail.log"
  #no keep
  no rewrite
  mda "/usr/bin/procmail -f %F -d %T";

Here is also few words on each of the .fetchmailrc config options

set daemon 600 The fetchmail binary with run in the background in daemon mod and fetch mail from the server every 600 seconds or 10 minutes.

set logfile fetchmail.log This will set the directory and file name of the fetchmail user log file. Eveytime fetchmail recieves an email, checks the pop3 server or errors out you will find an entry here.

poll the_isp_mail_server proto POP3 This line tells fetchmail what mail server to contact, in theis case "the_isp_mail_server" and to use the "POP3" protocol.

user "remote_user_name" pass "PASSWORD" is "local_username" preconnect "date >> fetchmail.log The user directive tells fetchmail what the name of the user on the remote mail server is for example "remote_user_name". The pass directive is simply the password you will use for the remote user on the mail server. The "is" directive is optional. It tells fetchmail to deliver mail to a diferent user name if the user on the remote mail server and the local machine are different. For example, I may be using the name "joe.doe" on the mail server, but my local user name is "jdoe". I would use a line like user "joe.doe" pass "PASSWORD" is "jdoe". The preconnect command simply adds the current time and date to the fetchmail log file every time fetchmail checks for new mail.

ssl The "ssl" directive tells fetchmail to use encryption when connecting to the pop3 mail server. Fetchmail will use port 995 instead of port 110 for un-encypted mail communication. In order to use ssl the remote mail server must be able to use ssl. Comment out this directive if you do _not_ use pop3s.

fetchall Fetchall just means to fetch all of the mail on the mail server no matter what the "read" flag is. It is possibly to read mail through many different processes. If you use another mail client from another location, for example you could have read you mail and kept it ont he server, but marked it with the "read" flag. At this point if you did _not_ use the "fetchall" flag then only mail marked as new would be downloaded.

no keep Once the mail is downloded from the mail server fetchmail is to tell the server to remove it from the server. You may choose to comment this option out if you want to leave all mail on the server.

no rewrite Do not rewrite headers. When fetchmail recieves the mail you do not want any of the headers mangled in any way. This directive tells fetchmail to leave the headers alone.

mda "/usr/bin/procmail -f %F -d %T"; The mda is your "mail delivery agent. Procmail is the program that fetchmail will hand the mail off to once it is downloaded. The argument "-f %F" logs who the mail if from and "-d %T" turns on explicit delivery mode, delivery will be to the local user recipient.

For configuring multiple mailboxes email to be gathered to local machine through fetchmail add to above configuration, some more config similar to this:

 poll protocol pop3:
       username "admin" password "your-plain-text-password" is "username" here;
       username "what-ever-user-name" password "Just-another-pass#" is "foreman" here;

  poll protocol pop3 with option sslproto '':
       user "whatever-user1" password "its-my-pass" mda "/usr/bin/procmail -d %T":   user "whatever-user1" password "its-my-pass" mda "/usr/bin/procmail -d %T


Because as you can see fetchmail keeps password in plaintext it is a best security practice to set some good file permissions on .fetchmailrc just to make sure some other local user on the same Linux / Unix machine will not be able to read your plaintext password, to do so issue below command.

chmod 600 ~/.fetchmailrc

For the purpose of logging as we have it into the config you will also need to create new blank file fetchmail.log

touch fetchmail.log

Once fetchmail all your emails you can use mail command to view your messages or further configure alpine or mutt to read the downloaded messages.

2. Use Alpine text based email client to check your downloaded email with fetchmail

Alpine is Text-based email client, friendly for novices but powerful
 Alpine is an upgrade of the well-known PINE email client.  Its name derives
 from the use of the Apache License and its ties to PINE.

In other words what Alpine is it is a rewritten and improved version of the good old PINE Unix email client (for those who remember it).

To give alpine a try on Debian / Ubuntu install it with:

apt-get install –yes alpine pilot


3. Use MuTT advanced and much more colorful text email client to view your emailbox


 Mutt is a sophisticated text-based Mail User Agent. Some highlights:
  * MIME support (including RFC1522 encoding/decoding of 8-bit message
    headers and UTF-8 support).
  * PGP/MIME support (RFC 2015).
  * Advanced IMAP client supporting SSL encryption and SASL authentication.
  * POP3 support.
  * ESMTP support.
  * Message threading (both strict and non-strict).
  * Keybindings are configurable, default keybindings are much like ELM;
    Mush and PINE-like ones are provided as examples.
  * Handles MMDF, MH and Maildir in addition to regular mbox format.
  * Messages may be (indefinitely) postponed.
  * Colour support.
  * Highly configurable through easy but powerful rc file.

To install MuTT:

linux:~# apt-get install –yes mutt

Configuring mutt if you don't have priorly set-up with fetchmail to collect your remote e-mails, you might want to try out .mutt's email fetch features to do so you will need a .muttrc configuration like that:

# Automatically log in to this mailbox at startup
set spoolfile="imaps://"
# Define the = shortcut, and the entry point for the folder browser (c?)
set folder="imaps://"
set record="=Sent"
set postponed="=Drafts"

You might also omit placing the password inside .muttrc configuration as storing the password in plaintext might be a big security hole if someone is able to read it at certain point, but the downside of that is you'll be asked by mutt to fill in your email password on every login which at a point becomes pretty annoying.

If you face problems with inability of mutt to connect to remote mail server due to TLS problems, you can also try to play with below configurations:

# activate TLS if available on the server
 set ssl_starttls=yes
 # always use SSL when connecting to a server
 set ssl_force_tls=yes
 # Don't wait to enter mailbox manually
 unset imap_passive        
 # Automatically poll subscribed mailboxes for new mail (new in 1.5.11)
 set imap_check_subscribed
 # Reduce polling frequency to a sane level
 set mail_check=60
 # And poll the current mailbox more often (not needed with IDLE in post 1.5.11)
 set timeout=10
 # keep a cache of headers for faster loading (1.5.9+?)
 set header_cache=~/.hcache
 # Display download progress every 5K
 set net_inc=5

Once you have the emails downloaded with fetchmail for your mailbox mutt should be showing your email stuff like in below screenshot

linux:~$ mutt


Of course a very handy thing to have is w3m-img text browser that displays images as it might be able to open your pictures attached to email if you're on a physical console tty.

I'll be curious to hear, if you know of better and easier solutions to check mail in console, so if you know such please drop a comment explaining how you check your mail text.

Disable Bluetooth on CentOS / RHEL (Redhat) / Fedora Linux servers – Disable hidd bluetooth devices

Thursday, January 29th, 2015


Bluetooth protocol on Linux is nice to have (supported) on Linux Desktop systems to allow easy communication wth PDAs, Tablets, Mobiles, Digital Cameras etc, However many newly purchased dedicated servers comes with Bluetooth support enabled which is a service rarely used, thus it is a good strong server security / sysadmin practice to remove the service supporting Blueetooth (Input Devices) on Linux hosts this is the hidd (daemon) service, besides that there are few Linux kernel modules to enable bluetooth support and removing it is also a very recommended practice while configuring new Production servers. 

Leaving Blueetooth enabled on Linux just takes up memory space and  potentially is a exposing server to possible security risk (might be hacked) remotely. 
Thus eearlier I've blogged on how bluetooth is disabled on Debian / Ubuntu Linux servers an optimization tuning (check) I do on every new server I have to configure, since administrating both RPM and Deb Linux distributions I usually also remove bluetooth hidd service support on every CentOS / RHEL / Fedora Linux – redhat  (where it is installed), here is how :

1. Disable Bluetooth in CentOS / RHEL Linux

a) First check whether hidd service is running on server:

[root@centos ~]# ps aux |grep -i hid

b) Disable bluetooth services

[root@centos ~]# /etc/init.d/hidd stop
[root@centos ~]# chkconfig hidd off
[root@centos ~]# chkconfig bluetooth off
[root@centos ~]# /etc/init.d/bluetooth off

c) Disable any left Bluetooth kernel module (drivers), not to load on next server boot

[root@centos ~]# echo 'alias net-pf-31 off' >> /etc/modprobe.conf

If you don't need or intend to use in future server USBs it is also a good idea to disable USBs as well:

[root@centos ~]# lsmod|grep -i hid
usbhid                 33292  0
hid                    63257  1 usbhid
usbcore               123122  4 usb_storage,usbhid,ehci_hcd

[root@centos ~]# echo 'usbhid' >> /etc/modprobe.d/blacklist.conf
[root@centos ~]# echo 'hid' >> /etc/modprobe.d/blacklist.conf
[root@centos ~]# echo 'usbcore' >> /etc/modprobe.d/blacklist.conf

2. Disable Bluetooth on Fedora Linux

Execute following:

[hipo@fedora ~]# /usr/bin/sudo systemctl stop bluetooth.service
[hipo@fedora ~]# /usr/bin/sudo systemctl disable bluetooth.service

3. Disable Bluetooth on Gentoo / Slackware and other Linuces

An alternative way to disable bluetooth that should work across all Linux distributions / versions is:

[root@fedora ~]# su -c 'yum install rfkill'
[root@fedora ~]# su -c 'vi /etc/rc.d/rc.local'

Place inside, something like (be careful not to overwrite something, already execution on boot):

rfkill block bluetooth
exit 0

4. Disable any other unnecessery loaded service on boot time

It is a good idea to also a good idea to check out your server running daemons, as thoroughfully as possible and remove any other daemons / kernel modules not being used by server.

To disable all unrequired services, It is useful to get a list of all enabled services, on RedHat based server issue:

[root@cento ~]#  chkconfig –list |grep "3:on" |awk '{print $1}'

 A common list of services you might want to disable if you're configuring (Linux, Apache, MySQL, PHP = LAMP) like server is:

chkconfig anacron off
chkconfig apmd off
chkconfig atd off
chkconfig autofs off
chkconfig cpuspeed off
chkconfig cups off
chkconfig cups-config-daemon off
chkconfig gpm off
chkconfig isdn off
chkconfig netfs off
chkconfig nfslock off
chkconfig openibd off
chkconfig pcmcia off
chkconfig portmap off
chkconfig rawdevices off
chkconfig readahead_early off
chkconfig rpcgssd off
chkconfig rpcidmapd off
chkconfig smartd off
chkconfig xfs off
chkconfig ip6tables off
chkconfig avahi-daemon off
chkconfig firstboot off
chkconfig yum-updatesd off
chkconfig mcstrans off
chkconfig pcscd off
chkconfig bluetooth off
chkconfig hidd off

In most cases you can just run script like this –

Another useful check the amount of services each of the running server daemons is using, here is how:

ps aux | awk '{print $4"t"$11}' | sort | uniq -c | awk '{print $2" "$1" "$3}' | sort -nr

Output of memory consumption check command is here

Quick way to access remotely your GNU / Linux Desktop – Access Linux Desktop from Mac and Windows 7

Tuesday, August 5th, 2014

For M$ Windows users its always handy to have remote access to your home PC or notebook via Remote Desktop (RDP) protocol.

However in GNU / Linux, there is no native implementation of RDP protocol. So if you're using Linux as your Desktop like me you will probably want to be able to access the Linux system remotely not only via terminal with SSH using (Putty) or MobaXTerm all in one tabbed Windows terminal program but also be able to use your Linux GNOME / KDE Graphical environment from anywhere on the Internet.

This will make you ponder – Is it possible to access Linux Desktop via proprietary RDP protocol and if not how you can achieve remote GUI access to Linux?

1. Using Linux Xorg and Xming Xserver for Windows

Most people should already know of Linux ability to start multiple Xserver sessions remotely which is the native way to access between two Linux hosts or access remotely Linux from other Linux UNIX like OS. It is also possible to use xinit / startx / xhost commands to establish remotely connection to new or running Linux (Xorg) Xserver by using them in combination with XMing – XServer for Windows running on the Windows host and Debian package (x11-xserver-utils) – providing xhost cmd, however this method is a bit complicated and not so convenient.

I used to be using this method XMing (whose mirror is here), earlier in my university years to use remotely my Debian Linux from  Windows 98 and this works perfectly fine.

2. Using RDP emulation with XRDP server

in order to be able to access your desk from any friend or computer club in the world using standard available in MS Windows Remote Desktop client (mstsc.exe).
There is also another alternative way by using Windows Desktop sharing RDP experimental server xrdp:

apt-cache show xrdp |grep -i descr -A 3
Description: Remote Desktop Protocol (RDP) server
 Based on research work by the rdesktop project, xrdp uses the Remote
 Desktop Protocol to present a graphical login to a remote client.
 xrdp can connect to a VNC server or another RDP server.

To make your Linux host accessible via RDP:

On Debian / Ubuntu etc. deb based Linux:

apt-get update
apt-get install xrdp

$ /etc/init.d/xrdp status
Checking status of Remote Desktop Protocol server xrdp                                             [ OK ]
Checking status of RDP Session Manager sesman

/etc/init.d/xrdp start

On  Fedora Linux:

yum -y install xrdp
systemctl enable xrdp.service
systemctl start xrdp.service
systemctl enable xrdp-sesman.service
systemctl start xrdp-sesman.service

It is possible to access remote Linux host using xrdp RDP server, but this will only work in older releases of mstsc.exe (Windows XP / Vista / 2003) and will not work on Windows 7 / 8, because in MS Windows 7 and onwards RDP proto version has changed and the client no longer has compatability with older mstsc releases. There is a work around for this for anyone who stubbornly want to use RDP protocol to access Linux host. If you want to connect to xrdp from Windows 7 you have to copy the old RDP client (mstsc.exe and mstscax.dll) from a WinXP install to the Windows 7 box and run it independently, from the default installed ones, anyways this method is time consuming and not really worthy …

3. Using the VNC withTightVNC server / client

Taking above in consideration, for me personally best way to access Linux host from Windows and Mac is to use simply the good old VNC protocol with TightVNC.

TightVNC is cross-platform free and open source remote Desktop client it uses RFB protocol to control another computer screen remotely.

To use tightvnc to access remote Debian / Ubuntu – deb based Linux screen, tightvncserver package has to be installed:

apt-cache show tightvncserver|grep -i desc -A 7
Description-en: virtual network computing server software
 VNC stands for Virtual Network Computing. It is, in essence, a remote
 display system which allows you to view a computing `desktop' environment
 not only on the machine where it is running, but from anywhere on the
 Internet and from a wide variety of machine architectures.

 This package provides a server to which X clients can connect and the
 server generates a display that can be viewed with a vncviewer.


apt-get –yes install tightvncserver

TightVNCserver package is also available in default repositories of Fedora / CentOS / RHEL and most other RPM based distros, to install there:

yum -y install tightvnc-server

Once it is installed to make tightvncserver running you have to start it (preferrably with non-root user), usually this is the user with which you're using the system:


You will require a password to access your desktops.

Would you like to enter a view-only password (y/n)? n

New 'X' desktop is rublev:4

Creating default startup script /home/hipo/.vnc/xstartup
Starting applications specified in /home/hipo/.vnc/xstartup
Log file is /home/hipo/.vnc/rublev:4.log


To access now TightVncserver on the Linux host Download and Install TightVNC Viewer client

note that you need to download TightVNC Java Viewer JAR in ZIP archive – don't install 32 / 64 bit installer for Windows, as this will install and setup TightVNCServer on your Windows – and you probably don't want that (and – yes you will need to have Oracle Java VM installed) …


Once unzipped run tightvnc-jviewer.jar and type in the IP address of remote Linux host and screen, where TightVNC is listening, as you can see in prior screenshot my screen is :4, because I run tightvnc to listen for connections in multiple X sessions. once you're connected you will be prompted for password, asker earlier when you run  tightvncserver cmd on Linux host.

If you happen to be on a Windows PC without Java installed or Java use is prohibited you can use TightVNC Viewer Portable Binary (mirrored here)


If you have troubles with connection, on Linux host check the exact port on which TightVncServer is running:

ps ax |grep -i Tightvnc

 8630 pts/8    S      0:02 Xtightvnc :4 -desktop X -auth /var/run/gdm3/auth-for-hipo-7dpscj/database -geometry 1024×768 -depth 24 -rfbwait 120000 -rfbauth /home/hipo/.vnc/passwd -rfbport 5904 -fp /usr/share/fonts/X11/misc/,/usr/share/fonts/X11/Type1/,/usr/share/fonts/X11/75dpi/,/usr/share/fonts/X11/100dpi/ -co /etc/X11/rgb

Then to check, whether the machine you're trying to connect from doesn't have firewall rules preventing the connection use (telnet) – if installed on the Windows host:

telnet 5904
Connected to
Escape character is '^]'.
RFB 003.008

telnet> quit
Connection closed.


Finding spam sending php scripts on multiple sites servers – Tracing and stopping spammer PHP scripts

Monday, April 14th, 2014

Spam has become a severe issue for administrators, not only for mail server admins but also for webshosting adms. Even the most secure spam protected mail server can get affected by spam due to fact it is configured to relay mail from other servers acting as web hosting sites.

Webhosting companies almost always suffer seriously from spam issues and often their mail servers gets blocked (enter spam blacklists), because of their irresponsible clients uploading lets say old vulnerable Joomla, WordPress without Akismet or proper spam handling plugin,a CMS which is not frequently supported / updated or custom client insecure php code.

What I mean is Shared server A is often configured to sent mail via (mail) server B. And often some of the many websites / scripts hosted on server A gets hacked and a spam form is uploaded and tons of spam start being shipped via mail server B.

Of course on mail server level it is possible to configure delay between mail sent and adopt a couple of policies to reduce spam, but the spam protection issue can't be completely solved thus admin of such server is forced to periodically keep an eye on what mail is sent from hosting server to mail server.

If you happen to be one of those Linux (Unix) webhosting admins who find few thousand of spammer emails into mail server logs or your eMail server queue and you can't seem to find what is causing it, cause there are multiple websites shared hosting using mainly PHP + SQL and you can't identify what php script is spamming by reviewing  Apache log / PHP files. What you can do is get use of:

PHP mail.log directive

Precious tool in tracking spam issues is a PHP Mail.log parameter, mail log paramater is available since PHP version >= 5.3.0 and above.
PHP Mail.log parameter records all calls to the PHP mail() function including exact PHP headers, line numbers and path to script initiating mail sent.

Here is how it is used:

1. Create empty PHP Mail.log file

touch /var/log/phpmail.log

File has to be writtable to same user with which Apache is running in case of Apache with SuPHP running file has to be writtable by all users.

On Debian, Ubunut Linux:

chown www:data:www-data /var/log/phpmail.log

On CentOS, RHEL, SuSE phpmail.log has to be owned by httpd:

chown httpd:httpd /var/log/phpmail.log

On some other distros it might be chown nobody:nobody etc. depending on the user with which Apache server is running.

2. Add to php.ini configuration following lines

mail.add_x_header = On
mail.log = /var/log/phpmail.log

PHP directive instructs PHP to log complete outbund Mail header sent by mail() function, containing the UID of the web server or PHP process and the name of the script that sent the email;

(X-PHP-Originating-Script: 33:mailer.php)

i.e. it will make php start logging to phpmail.log stuff like:

mail() on [/var/www/pomoriemonasteryorg/components/com_xmap/2ktdz2.php:1]: To: — Headers: From: "Priority Mail" <status_93@pomoriemon> X-Mailer: MailMagic2.0 Reply-To: "Priority Mail" <> Mime-Version: 1.0 Content-Type: multipart/alternative;boundary="——
mail() on [/var/www/pomoriemonasteryorg/components/com_xmap/2ktdz2.php:1]: To: — Headers: From: "One Day Shipping" <status_44@pomoriemonastery.
org> X-Mailer: CSMTPConnectionv1.3 Reply-To: "One Day Shipping" <> Mime-Version: 1.0 Content-Type: multipart/alternative;boundary="—
mail() on [/var/www/pomoriemonasteryorg/components/com_xmap/2ktdz2.php:1]: To: — Headers: From: "Logistics Services" <customer.> X-Mailer: TheBat!(v3.99.27)UNREG Reply-To: "Logistics Services" <> Mime-Version: 1.0 Content-Type: mult
mail() on [/var/www/pomoriemonasteryorg/components/com_xmap/2ktdz2.php:1]: To: — Headers: From: "Priority Mail" <status_73@pomoriemonaster> X-Mailer: FastMailer/Webmail(versionSM/1.2.6) Reply-To: "Priority Mail" <> Mime-Version: 1.0 Content-Type: multipart/alternativ

On Debian / Ubuntu Linux to enable this logging, exec:

echo 'mail.add_x_header = On' >> /etc/php5/apache2/php.ini
echo 'mail.log = /var/log/phpmail.log' >> /etc/php5/apache2/php.ini

I find it useful to symlink /etc/php5/apache2/php.ini to /etc/php.ini its much easier to remember php location plus it is a standard location for many RPM based distros.

ln -sf /etc/php5/apache2/php.ini /etc/php.ini

Or another "Debian recommended way" to enable mail.add_x_header logging on Debian is via:

echo 'mail.add_x_header = On' >> /etc/php5/conf.d/mail.ini
echo 'mail.log = /var/log/phpmail.log' >> /etc/php5/conf.d/mail.ini

On Redhats (RHEL, CentOS, SuSE) Linux issue:

echo 'mail.add_x_header = On' >> /etc/php.ini
echo 'mail.log = /var/log/phpmail.log' >> /etc/php.ini

3. Restart Apache

On Debian / Ubuntu based linuces:

/etc/init.d/apache2 restart

P.S. Normally to restart Apache without interrupting client connections graceful option can be used, i.e. instead of restarting do:

/etc/init.d/apache2 graceful

On RPM baed CentOS, Fedora etc.:

/sbin/service httpd restart


apachectl graceful

4. Reading the log

To review in real time exact PHP scripts sending tons of spam tail it:

tail -f /var/log/phpmail.log

mail() on [/var/www/remote-admin/wp-includes/class-phpmailer.php:489]: To: — Headers: Date: Mon, 14 Apr 2014 03:27:23 +0000 Return-Path: From: WordPress Message-ID: X-Priority: 3 X-Mailer: PHPMailer ( [version 2.0.4] MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="UTF-8"
mail() on [/var/www/pomoriemonasteryorg/media/rsinstall_4de38d919da01/admin/js/tiny_mce/plugins/inlinepopups/skins/.3a1a1c.php:1]: To: — Headers: From: "Manager Elijah Castillo" <> X-Mailer: Mozilla/5.0 (Windows; U; Windows NT 5.0; es-ES; rv: Gecko/20100111 Thunderbird/3.0.1 Reply-To: "Manager Elijah Castillo" <> Mime-Version: 1.0 Content-Type: multipart/alternative;boundary="———-1397463670534B9A76017CC"
mail() on [/var/www/pomoriemonasteryorg/media/rsinstall_4de38d919da01/admin/js/tiny_mce/plugins/inlinepopups/skins/.3a1a1c.php:1]: To: — Headers: From: "Manager Justin Murphy" <> X-Mailer: Opera Mail/10.62 (Win32) Reply-To: "Manager Justin Murphy" <> Mime-Version: 1.0 Content-Type: multipart/alternative;boundary="———-1397463670534B9A7603ED6"
mail() on [/var/www/pomoriemonasteryorg/media/rsinstall_4de38d919da01/admin/js/tiny_mce/plugins/inlinepopups/skins/.3a1a1c.php:1]: To: — Headers: From: "Manager Elijah Castillo" <> X-Mailer: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; pl; rv: Gecko/20100317 Thunderbird/3.0.4 Reply-To: "Manager Elijah Castillo" <> Mime-Version: 1.0 Content-Type: multipart/alternative;boundary="———-1397463670534B9A7606308"
mail() on [/var/www/pomoriemonasteryorg/media/rsinstall_4de38d919da01/admin/js/tiny_mce/plugins/inlinepopups/skins/.3a1a1c.php:1]: To: — Headers: From: "Manager Justin Murphy" <> X-Mailer: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; pl; rv: Gecko/20100317 Thunderbird/3.0.4 Reply-To: "Manager Justin Murphy" <> Mime-Version: 1.0 Content-Type: multipart/alternative;boundary="———-1397463670534B9A76086D1"

As you can see there is a junky spam mails sent via some spammer script uploaded under name .3a1a1c.php, so to stop the dirty bastard, deleted the script:

rm -f /var/www/pomoriemonasteryorg/media/rsinstall_4de38d919da01/admin/js/tiny_mce/plugins/inlinepopups/skins/.3a1a1c.php

It is generally useful to also check (search) for all hidden .php files inside directoring storing multiple virtualhost websites, as often a weirdly named hidden .php is sure indicator of either a PHP Shell script kiddie tool or a spammer form.

Here is how to Find all Hidden Perl / PHP scripts inside /var/www:

find . -iname '.*.php'

find . -iname '.*.pl*'


Reviewing complete list of all hidden files is also often useful to determine shitty cracker stuff

 find . -iname ".*"

Debugging via  /var/log/phpmail.log enablement is useful but is more recommended on development and staging (QA) environments. Having it enable on productive server with high amounts of mail sent via PHP scripts or just on dedicated shared site server could cause both performance issues, hard disk could quickly get and most importantly could be a severe security hole as information from PHP scripts could be potentially exposed to external parties.

FastStone nice alternative picture freeware viewer software to Windows Photo Viewer

Tuesday, October 22nd, 2013

Faststone Windows 7 Vista Win 8 free good picture iewer program logo
I'm forced to use Windows in my work place in HP and occasionally have to open pictures. Default Windows viewer Windows Photo Viewer is very limited in what it can do. It can't even Rotate a picture so I find it a good idea to find a good alternative. Historically I liked to use IrfanView Freeware but I saw a colleague to use FastStone Image Viewer and I decided to give it a try. It looks more function rich than IrfanView so I install it and intend to use it as primary picture viewer on HP work Elitebook 8470p with Windows 7

Irfanview windows 8 picture viewer alternative to default Microsoft Picture Viewer screenshot

I strongly recommend the program to anyone looking for a good alternative to 'woody' Windows Image Viewer and who for some reason wants alternative to Irfanview.

FastStone has all the basic features I need like Crop image, Rotate Image etc. by using it I don't have to run GIMP for simple image manipulations. Another good reason to use FastStone is many of well known shortcut keys are similar to Proprietary (Non-Free) ACDSee which I used to heavily used in old days when I was still using Windows 98 so it feels using it quite confortable. Other thing is FastStone manages quite well non-standard RAW formats from various Cameras.

FastStone image pictureviewer windows good windows Image Viewer alternative to Windows default image viewer program and IrfanView
FastStone has even a bunch of standard Effects to apply to a picture, play with Shadows Lightning and most of basic professional File manipulation embedded. Hope someone will benefit out of the post and will start using it.


Disable bluetooth on Linux IBM / Lenovo Thinkpad laptops

Thursday, February 14th, 2013

bluetooth gnu linux disable bluetooth linux how to tux logo bluetooth thinkpad

I have a Debian GNU / Linux squeeze with bluetooth and bluetooth is started automatically on system boot. This is pretty annoying, cause I use bluetooth quite rarely.
 disable / enable bluetooth via terminal is controlled via Linux sysfs virtual filesystem. The command to disable bluetooth one time is:

debian:~# echo 0 > /sys/devices/platform/thinkpad_acpi/bluetooth_enable

It is efficient in terms of energy saving especially if you use often your notebook on battery to turn off bluetooth permanently and only enable it when needed with:

debian:~# echo 1 > /sys/devices/platform/thinkpad_acpi/bluetooth_enable

To permanently disable bluetooth on Linux boot use:

# service bluetooth stop

In /etc/rc.local before exit 0 line place:

echo 0 > /sys/devices/platform/thinkpad_acpi/bluetooth_enable

An alternative method to permanently disable bluetooth (on other non-Thinkpad – any brand laptops) is via rfkill (bluetooth device control interface), on Ubuntu rfkill is installed by default but Debian users has to explicitly install it via apt:

debian:~# apt-get install –yes rfkill

Once rfkill is installed on host put a line before exit 0 in /etc/local:

rfkill block bluetooth