Posts Tagged ‘working’

Update reverse sshd config with cronjob to revert if sshd reload issues

Friday, February 12th, 2021

Reading Time: 2 minutes

Update-reverse-sshd-config-with-cronjob-to-revert-if-sshd-reload-issues

Say you're doing ssh hardening modifying /etc/ssh/sshd_config for better system security or just changing options in sshd due to some requirements. But you follow the wrong guide and you placed some ssh variable which is working normally on newer SSH versions ssh OpenSSH_8.0p1 / or 7 but the options are applied on older SSH server and due to that restarting sshd via /etc/init.d/… or systemctl restart sshd cuts your access to remote server located in a DC and not attached to Admin LAN port, and does not have a working ILO or IDRAC configured and you have to wait for a couple of hours for some Support to go to the server Room / Rack / line location to have access to a Linux physical tty console and fix it by reverting the last changes you made to sshd and restarting.

Thus logical question comes what can you do to assure yourself you would not cut your network access to remote machine after modifying OpenSSHD and normal SSHD restart?

There is an old trick, I'm using for years now but perhaps if you're just starting with Linux as a novice system administrator or a server support guy you would not know it, it is as simple as setting a cron job for some minutes to periodically overwrite the sshd configuration with a copy of the old working version of sshd before modification.

Here is this nice nify trick which saved me headache of call on technical support line to ValueWeb when I was administering some old Linux servers back in the 2000s

root@server:~# crontab -u root -e

# create /etc/ssh/sshd_config backup file
cp -rpf /etc/ssh/sshd_config /etc/ssh/sshd_config_$(date +%d-%m-%y)
# add to cronjob to execute every 15 minutes and ovewrite sshd with the working version just in case
*/15 * * * * /bin/cp -rpf /etc/ssh/sshd_config_$(date +%d-%m-%y) /etc/ssh/sshd_config && /bin/systemctl restart sshd
# restart sshd 
cp -rpf /etc/ssh/sshd_config_$(date +%d-%m-%y) /etc/ssh/sshd_config && /bin/systemctl restart sshd


Copy paste above cron definitions and leave them on for some time. Do the /etc/ssh/sshd_config modifications and once you're done restart sshd by lets say

root@server:~#  killall -HUP sshd 


If the ssh connectivity continues to work edit the cron job again and delete all lines and save again.
If you're not feeling confortable with vim as a text editor (in case you're a complete newbie and you don't know) how to get out of vim. Before doing all little steps you can do on the shell with  export EDITOR=nano or export EDITOR=mcedit cmds,this will change the default text editor on the shell. 

Hope this helps someone… Enjoy 🙂

Configure rsyslog buffering on Linux to avoid message lost to Central Logging server

Wednesday, January 13th, 2021

Reading Time: 2 minutes

rsyslog-Centralized-Logging-System-using-Rsyslog_logo

1. Rsyslog Buffering

One of the best practice about logs management is to send syslog to a central server. However, a logging system should be capable of avoiding message loss in situations where the server is not reachable. To do so, unsent data needs to be buffered at the client when central server is not available. You might have recently noticed that many servers forwarding logs messages to a central server do not have buffering functionalities activated. Thus I strongly advise you to have look to this documentation to know how to check your configuration: http://www.rsyslog.com/doc/rsyslog_reliable_forwarding.html

Rsyslog buffering with TCP/UDP configured

In rsyslog, every action runs on its own queue and each queue can be set to buffer data if the action is not ready. Of course, you must be able to detect that "the action is not ready", which means the remote server is offline. This can be detected with plain TCP syslog and RELP, but not with UDP. So you need to use either of the two. In this howto, we use plain TCP syslog.

– Version requirement

Please note that we are using rsyslog-specific features. The are required on the client, but not on the server. So the client system must run rsyslog (at least version 3.12.0), while on the server another syslogd may be running, as long as it supports plain tcp syslog.

How To Setup rsyslog buffering on Linux

First, you need to create a working directory for rsyslog. This is where it stores its queue files (should need arise). You may use any location on your local system. Next, you need to do is instruct rsyslog to use a disk queue and then configure your action. There is nothing else to do. With the following simple config file, you forward anything you receive to a remote server and have buffering applied automatically when it goes down. This must be done on the client machine.

# Example:
# $ModLoad imuxsock             # local message reception
# $WorkDirectory /rsyslog/work  # default location for work (spool) files
# $ActionQueueType LinkedList   # use asynchronous processing
# $ActionQueueFileName srvrfwd  # set file name, also enables disk mode
# $ActionResumeRetryCount -1    # infinite retries on insert failure
# $ActionQueueSaveOnShutdown on # save in-memory data if rsyslog shuts down
# *.*       @@server:port

A quick and easy way to install Social Network on Linux/BSD System with Elgg

Monday, March 14th, 2011

Reading Time: 3 minutes

elgg-blue-logo
I'm experimenting this days with Elgg – An Open Source Free Software GPLed Social Network which enables users to quickly create Communities.

Elgg is really easy to install and all it requires is a Linux/BSD or Windows system with PHP, MySQL and Apache installed.

Elgg is provided with dozens of nice plugins which for a short time enables individual to create fully operational Social Network like facebook.

Many people nowdays use facebook without realizing how bad facebook is how it breaks their privacy.
Facebook is actually a spy network, it stores data and pictures, likings and user behaviour of million of users around the world.
This needs to be stopped somehow, maybe if people start using the free software networks like elgg to build a mini-community which has profound interests in a certain spheres of work, life and amusement.
The evil empire of facebook will slowly start to loose it's position and the small projects networks based on Elgg and the other Free Software Social Networks which are currently available will start to rise up.
I'm currently really a novice into Elgg but I'm more convinced that the guys who develop it and contribute to it in terms of handy plugins have done really a great job.

It's ultra easy even for non professional middle level user to setup himself an Elgg install.
The installation procedure is not much harder than a simple wordpress blog or joomla based website install.
The installation of elgg takes no more than 10 to 20 minutes, the plugin installation and setup time further could take few days but in the end you have a full featured Social Network! This is really amazing.
The installation of new plugins in elgg is also fool proof / easy all you have to do to equip a newly installed elgg with plugins is to go to it's root directory and look for the mod directory. The new plugins which needs to be installed, could be directly downloaded and saved via links, elinks, lynx or even wget to the elgg installation directory.

Most of the elgg plugins comes in a form of zip files so after being installed simply executing:

server:/home/elgg/mysocialnetwork/mod# unzip walltowall.zip
....

The above cmd will for example unzip the WallToWall elgg plugin and the plugin will be further ready to be enabled via the administrator user set upped during your elgg installation.

The configurations of elgg are being accomplished via:

Administration -> Tool Administration

I should I'm still experimenting with Elgg social, until this very moment I've installed the following elgg plugins:

aaudio
akismet
artfolio
blog
bookmarks
buddytalk
captcha
categories
chat
crontrigger
custom_index
custom_profile_fields
default_widgets
diagnostics
elgg-ebuddy
embed
embedvideo
emoticons
externalpages
family
fbconnect
file
file_tree
flyers
forum
friend_request
friends
garbagecollector
groups
htmlawed
invitations
invitefriends
izap_videos
kaltura_video
lastfm
likes
logbrowser
logrotate
lucygames
members
messageboard
messages
milockergames_frameme
noscript_message
notifications
pages
polls
profile
reportedcontent
resume
river_comments
riverdashboard
riverfaces
search
siteaccess
tagcloud
theme_simpleneutral
thewire
tidypics
tidypicsExt
tinymce
twitter
twitterservice
user_contact_list
uservalidationbyemail
walltowall
weather
wp1
zaudio

One very handy feature I truly enjoy about Elgg is that it gives every user an own blog which or in other words when somebody registers in Elgg, he automatically gets a personal blog! How cool this is Yeash 😉
The Elgg photo upload plugin is also another interesting story. The photo plugin is a way better from my first impressions than facebook's buggy upload client.
Elgg also uses heavily jquery for it's various operations and the user experience feels very interactive.

Of course as with all free software things are not perfect some of the elgg plugins or (mods) as they are called are not working.
For example I couldn't make by so far the weather plugin which is supposed to report the weather.

Maybe some tweakening of the not working plugins will easily make them working. What is really important is that the Elgg basis system looks and seems to work really good and enpowers the user with a social network alternatives to the ugly facebook.

In order to experiment with Elgg and I've established a small social network targetting at University College and School Students called MockATeacher – mockateacher.com>/i>. The idea behind is to help students in their report writting by providing them with a place where they can meet other students and share files.

Some other aspects I've planned for MockATeacher is to build a small community of people who would like to share about idiot teachers, teacher stupid sayings as well as to mock the idiotic type of education that we and our children are up to in this age.
Just to close up, if you're looking for some time to spend in experimenting in an enjoyable way you definitely need to install elgg and play with it 😉


Remove pre-installed HP, Dell, Asus, Acer, Toshiba not needed default vendor software on a new bought PC notebook quickly with Decrap My Computer

Thursday, April 14th, 2016

Reading Time: 4 minutes

remove-default-unneded-software-from-manufacturer-hp-asus-acer-dell-toshiba
While browsing today and looking for software to clean up all the spy software from my corporate HP laptop, I've come across an interesting tool called Decrap which aims at removing Bloatware from a Windows PC / notebook (mirrored here because original software site was down)

So what is Bloatware ?

The term Bloatware (also called jokingly crapware) is term is the one that was coined to describe, the default pre-installed software that comes to you together with Windows pre-installed OS by the hardware manufacturer.
I'm sure anyone who bought brand new branded PC or laptop over the last 10 years have already suffered the unwanted and unnecessery
bunch of software that comes pre-installed freeware programs aiming to help you in your daily work but in reality just slowing down your PC
and showing annoying popups or at best keeping useless in Windows system apptray.

Let me give you an example:

Cleanup (Remove) common ASUS, HP, Dell default  installed unneded (Bloatware) software

Many users may want to uninstall ASUS Crapware software such as ASUS Tutor, ASUS LifeFrame3, ASUS WebStorage and ASUSVibe.

Like Asus, HP computers often come preloaded with useless software from factory, example for this is HP Customer Service enhancements, HP Update, HP Total Care Setup and ProtectSmart.

If you buy Dell PC notebook soon you'll discover that there are several preloaded software (often unnecessery software) such as Dell Stage, Dell Digital Delivery and Dell DataSafe.

Toshiba computers and notebooks contain pre-loeaded "crapware" software from Toshiba.
Just to mention a few of those: Toshiba Disc Creator, Toshiba ReelTime, Service Station, Bulletin Board and Toshiba Assist.

Often there are fingerprint reader programs, Wi-Fi connection managers, Bluetooth managers, Audio Management sofware and other third party vendor software which tend to be not working as good as others softwares from third vendor, so Decrap is to help you to identify and remove these too in a easy GUI manner.

Non-experienced Computer users often leave the bloatware to hang around for even years and only if some relative that is an IT involved person / sysadmin / Even once you're aware that the Bloatware is on the system the ordinary user is hard to remove it as he is scared not to break the system.
Besides that fften this bloatware just soft comes so much integrated into Windows that removing it costs hours of tries and research online on
all the Bloatware components and even then could mislead you so you break the PC. programmer etc. comes home of such users finds out about the happily existing of the useless software on the notebook.


So here is Decrap My Computer coming at place aiming to help to remove the unnecessery Hardware vendor software in few easy (Click, Click, Click Next ..) steps.

decrap-my-computer-clean-up-bloatware-crapware-on-windows-laptop-main-gui

Then decrap does silently all the complex operations and suggestions to make the HP, Dell, Asus, Toshiba manufacturer prebundled software to be stopped and uninstalled.
Decrap My Computer is a freeware, lightweight and easy to use and lets you safely remove crapware and bloatware, or any software, from any Windows PC.

Even for Old computers, Decrap comes handy for the unexperienced avarage user who used his laptop with this useless  default vendors programs silently killing the performance respectively user experience for years.

Using Decrap is quite intuitive PC is scanned for Bloatware and then after a backup Windows Restore Point is offered you're offered to review and Uninstall the unwanted softwares. There is also an automatic mode but those one still could be a bit dangerous, so use the automatic mode only on multiple machines with the same model  / brand notebooks that comes prebundled with same sofware after testing and confirming the automatic mode on 1 initial machine will not break up some needed functionality.

decrap-your-pc-clean-up-windows-from-hp-dell-toshiba-asus-bloatware-unuseful-programs

Here is few screenshots of the tool in action:
decrap-choose-what-default-laptop-manufacturer-software-you-want-to-clean-from-new-bought-pc

decrap-choose-what-default-laptop-manufacturer-software-you-want-to-clean-from-new-bought-pc-1

decrap-choose-what-default-laptop-manufacturer-software-you-want-to-clean-from-new-bought

Another good alternative (since decrap seems to be not maintained anymore) as I just leardned from Natasha Myles (thanks for pointing me about the broken link to decrap website) is SpeedUpPC more on speeding up old PC or laptop is her article 


What Every Body is Saying – one of Best books on Body Language ever written

Tuesday, August 14th, 2018

Reading Time: 5 minutes

how-to-learn-to-read-people-and-become-a-better-communicator-What-every-body-is-saying-book-cover

Those interested in People Reading or holding a Management position position job inside some Small or Mid sized corporation could benefit greatly of a Book called
What Every Body is Saying

What Every Body is Saing is written by an ex-FBI Agent (JOE NAVANNO), probablythere are no actually ex-FBI agents, but that's a topic for another post.

The book is quick to read, especially if you follow the pictures of Body postures shown with their little description below.
Many of the Body Languages so commonly adopted by multitudes of people, thanks to the American of the Culture world-wide are being practiced
in some degree in mostly all people you might know (mostly unconsciously) …


What Every Body is Saying could be of a great help to people who want to make through in life and for Start-up company CEOs, Human Resource Managers, or anyone who want to better learn to communicate and Influence People.

Even in a normal family relations, being able to properly identify the Body Language of your Wife or kids would seriously benefit you and if you keep attention (focus) would reveal there short term-plans.

what-sitting-posture-is-sayingbook-what-every-body-is-saying

Adopting some of the suggested body languages in the book would definitely help you improve how people perceive you and practising some so called "Confident postures" could even boost your Confidence levels dramatically both when you're alone or when you are in a group of people or A Company Team Meeting.

Reading the Person Body language is of a great help also to understand the approximate Emotional / Spiritual state the person in front of you is and even if applied proparly could help you make the person or group of people be positively influenced to change from a negative to positive mindset
or when working on a project, could help you dramatically to make the people work more efficiently and boost their motivation / mood about the things, they have to someday do anyways.

The reader has to know of course that most of the mentioned body language cues are generalizations and in order to find out the exact messages being sent on non-verbal communication level depends on a multiple factors and many of the Body languages talked might be in a modified form and even some could be totally different from any of the described of the book.

However the observation practice (at least mine) shows that at least 60-70% of the described Body Language postures are adopted and used by mostly anyone out there.
To check the validity of the things described in the books just sit somewhere in a park or in a bar / caffeteria and watch carefully how people interact, you will be surprised how many things are being communicated non-verbally and how often the lack of one of the two, or two have severe communication issues, just because they couldn't synchronize their body language or lack the ability to read the other interlocutor's processed and communicated intentions.

The book when red at least for me was a wide eyes opener and even though as a Christian, I've always been doubting that any-generalization model trying to frame up people is very untrue and trying to influence people with your Body Language is bad sinful (kinda of satanic) practice, realizing that even Christians does communicate and do use body language (because they're conditioned by the society they lived in), that means that improving your Body Language to be more convincing in mostly anti-christian society we live can do you good favour to be adequate in society, or at least you can be aware of the existence of the Body Language and its meaning.

By the way, many of the models and gestures as translated described as a behaviour body interpretations are perhaps highly used nowadays by Agents across all the major Secret Services agencies such as CIA, MI6, KGB, Mussad etc.

book-what-every-body-is-saying_or-how-to-improve-your-daily-relations-by-reading-people

This kind of things are learned in most business universities nowadays, but the way the Body Reading / Influencing knowledge is communicated in Business universities is a disaster, because it is usually compiled by Professors who alone are not expert or haven't been advanced enough in body language.
Thus even like that if you read the book, I'm sure you will benefit and perhaps reread it at least a couple of times in the coming years …

A summary of the book goes like this:

1. It starts with a short story on how the author get acquainted to the knowledge of body language and his personal life events

The author Joe Navarro was an emigrant from Cuba to US as the age of 8, because the author inability to speak English at all, his best way to understand what the other was saying or communicating in the first few years in US was to observe closely what the person in front was communicating non-verbally and makes guesses, what that could be.
His family and grandmother also played a key role to help him learn the craft of Body Language reaading.

Growing up and graduating college in the age of Baby Boomers, Joe Navarro was hired in FBI where he spend the following years as an agent specializing in Counter Intelligence
and behavior assessment.

2. It continues as the knowledge on Body interprations is being served in a very stuffed manner

 

what-everybody-is-saying-back-book-cover

The 3 key things to remember out of the book goes like that:

    A. At least 60% of what you say is not coming out of your mouth.
    B. There’s one more option next to fight or flight responce our brain does automatically
    C. To become a master at reading body language, you have to develop situational awareness.

The book claims that people tend to be stuck into 3 main states (as a result of the evolutionary development of species (Creationists and Christian fundamentalists could argue seriously here 🙂 ) , whenever facing a difficult situation these are:

  • Freeze
  • Fight
  • Flight

To sum up if you're looking for new ways to improve your current relationships with people and build a new ones, the book would definitely help you tremendously.
I've found the book in a PDF format with few simple searches online so those who can't afford it could also download it from the internet (at least as of time of writting this article).
A lot of the exampled Body confidence / influence postures described in the book you will find on mostly any Kids Cartoon and Internet top shows and in mostly everybody from TED Talks show and mostly all Youtube educational videos and podcasterers.

That's all Folks, Enjoy reading!

 

 

Fix qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied – Finally a working solution and what causes the error

Wednesday, July 22nd, 2015

Reading Time: 7 minutes

 

qmail-fixing-clamdscan-errors-and-qq-errors-qmail-binary-migration-few-things-to-check-out
I've lost a whole day and was angry and irritated after moving (migrating) a Working Qmail installation in a binary form from a Debian Lenny 5.0 to a Debian 7.0 Wheezy Linux. The whole migration exercise was quite of a crazy move and I can tell you it didn't worth the effort as I lost much more time than even if I went on installing the server following Thibs Great Qmail Tutorial.

Yes I know many would say why do you still bother with an old and unsupported Qmail Mail server and not go with Postfix, the logic is correct however the whole issue is the previous installation has a number of domains already running VirtualMail hosting using VPopMail, so migrating all the old mailboxes from Qmail to Postfix are not worthy IMHO. Plus I honestly love qmail for being so stable even today (even without support). After all most of Qmail is secure enough already 🙂
And to be honest I don't so much care about security as in the old days as I know NSA, does already have access to any server on planet 🙂

Almost always when a Qmail migration happens I end up swearing and sweating and generally getting crazy, but anyways …

The overall migration of binaries went quite OK I just copied every binary and all the related libraries from the old Debian 5.0 to Debian 7.0 and installed the following long list of perl deb binaries using apt-get:
 

dh-make-perl
libalgorithm-c3-perl
libalgorithm-diff-perl
libalgorithm-diff-xs-perl
libalgorithm-merge-perl
libapparmor-perl
libapt-pkg-perl
libarray-unique-perl
libclass-accessor-chained-perl
libclass-accessor-perl
libclass-c3-perl
libclass-c3-xs-perl
libclass-factory-util-perl
libclass-inspector-perl
libclass-isa-perl
libclass-load-perl
libclass-singleton-perl
libconfig-file-perl
libconvert-binhex-perl
libcrypt-openssl-bignum-perl
libcrypt-openssl-random-perl
libcrypt-openssl-rsa-perl
libcrypt-passwdmd5-perl
libcrypt-ssleay-perl
libdata-optlist-perl
libdata-section-perl
libdate-manip-perl
libdatetime-format-builder-perl
libdatetime-format-iso8601-perl
libdatetime-format-strptime-perl
libdatetime-locale-perl
libdatetime-perl
libdatetime-timezone-perl
libdbd-mysql-perl
libdbi-perl
libdevel-symdump-perl
libdigest-hmac-perl
libdigest-sha-perl
libdpkg-perl
libemail-address-perl
libemail-date-format-perl
libencode-detect-perl
libencode-locale-perl
libenv-sanctify-perl
liberror-perl
libexporter-lite-perl
libfcgi-perl
libfile-chdir-perl
libfile-fcntllock-perl
libfile-find-rule-perl
libfile-listing-perl
libfile-which-perl
libfont-afm-perl
libhtml-form-perl
libhtml-format-perl
libhtml-parser-perl
libhtml-tagset-perl
libhtml-template-perl
libhtml-tree-perl
libhttp-cookies-perl
libhttp-daemon-perl
libhttp-date-perl
libhttp-message-perl
libhttp-negotiate-perl
libhttp-server-simple-perl
libio-multiplex-perl
libio-socket-inet6-perl
libio-socket-ip-perl
libio-socket-ssl-perl
libio-string-perl
libio-stringy-perl
libip-country-perl
liblist-moreutils-perl
liblocale-gettext-perl
liblwp-mediatypes-perl
liblwp-protocol-https-perl
libmail-dkim-perl
libmail-sendmail-perl
libmail-spf-perl
libmailtools-perl
libmath-round-perl
libmime-tools-perl
libmodule-depends-perl
libmodule-implementation-perl
libmodule-runtime-perl
libmro-compat-perl
libnet-cidr-lite-perl
libnet-cidr-perl
libnet-daemon-perl
libnet-dns-perl
libnet-http-perl
libnet-ident-perl
libnet-ip-perl
libnet-server-perl
libnet-snmp-perl
libnet-ssleay-perl
libnetaddr-ip-perl
libnumber-compare-perl
libossp-uuid-perl
libpackage-deprecationmanager-perl
libpackage-stash-perl
libpackage-stash-xs-perl
libparams-classify-perl
libparams-util-perl
libparams-validate-perl
libparse-debcontrol-perl
libparse-debianchangelog-perl
libparse-syslog-perl
libpcre-ocaml-dev
libpcre3:amd64
libpcre3-dev
libpcrecpp0:amd64
libperl-dev
libperl5.14
libpod-coverage-perl
libregexp-assemble-perl
librpc-xml-perl
librrds-perl
libsoap-lite-perl
libsocket-perl
libsocket6-perl
libsoftware-license-perl
libsub-exporter-perl
libsub-install-perl
libsub-name-perl
libswitch-perl
libsys-hostname-long-perl
libsys-syslog-perl
libtask-weaken-perl
libterm-readkey-perl
libtest-distribution-perl
libtest-pod-coverage-perl
libtest-pod-perl
libtext-charwidth-perl
libtext-glob-perl
libtext-iconv-perl
libtext-template-perl
libtext-wrapi18n-perl
libtie-ixhash-perl
libtimedate-perl
libtry-tiny-perl
liburi-perl
libwww-mechanize-perl
libwww-perl
libwww-robotrules-perl
libxml-namespacesupport-perl
libxml-parser-perl
libxml-sax-base-perl
libxml-sax-expat-perl
libxml-sax-perl
libxml-simple-perl
libyaml-perl
libyaml-syck-perl
perl
perl-base
perl-doc
perl-modules
spamassassin
spf-tools-perl

 

I've also installed with apt-get daemontools and daemontools-run ucspi and some others to get all the necessery binaries qmail needs the whole list of apt installed packages is here

I've also copied all the old binaries from /usr/local/lib from server1 to server2, some others from /usr/local/share and /usr/share as well as /usr/lib/courier /usr/lib/courier-authlib /usr/local/libexec /usr/local/sbin also had to link a couple of libraries such as /usr/lib/libcrypto* , link  /usr/lib/libperl.so.5.10 to /usr/lib/libperl.so.5.14 and copy /usr/lib/libltdl.so.3 and few others which i don't exactly remember.

Well anyways once I've copied everything Qmail looked fined except I had a couple of permission issues and had to clean up and fix the queue with qfixq, I've also used qmail-scanner*/contrib/test_installation.sh script to test whether qmail-scanner was running fine, e.g.:
 

./test_installation.sh -doit


As well as

 

 

qmr_inst_check


script, thanks to which I've captured and resolved few of permission problems 

Finally I've stuck upon this shitty errors (appearing) in /var/log/syslog and /var/log/messages

 

 

Jul 21 22:04:19 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:08:27 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:08:38 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:11:17 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:16:09 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:19:15 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:38:59 ns2 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:42:33 ns2 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:43:49 ns2 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:46:05 ns2 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:50:40 ns2 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied
Jul 21 22:53:08 ns2 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied

 

 

 

There is plenty of things written about this:
 

qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[] cannot create /var/spool/qscan/tmp – Permission denied


But all written is too obscure and too old already somewhere between 2004 and 2010, I've been digging through Gentoo Forums, Fedora Debian and other Linux installs and everyone used to be pointing a permission issue with /var/spool/qscan/ said theoretically to be causing the error, however all looked perfectly fine with my /var/spool/qscan , e.g.:

 

 

roo@ns2:/usr/local/src# ls -ld /var/spool/qscan/
drwxr-s— 6 qscand qscand 4096 Jul 21 23:07 /var/spool/qscan/

 

 

 

 

ls -al /var/spool/qscan/
total 244904
drwxr-s— 6 qscand qscand      4096 Jul 21 23:07 .
drwxr-xr-x 4 root   root        4096 Jul 20 21:17 ..
drwxrwx— 5 qscand qscand      4096 Oct 12  2011 archives
-rwxr-x— 1 qscand qscand      1434 Oct 12  2011 log-report.sh
-rw——- 1 qscand qscand 249731919 Jul 21 23:11 qmail-queue.log
-rw——- 1 qscand qscand    398225 Oct 28  2011 qmail-queue.log.1
-rw-rw—- 1 root   qscand        74 Jul 21 23:07 qmail-scanner-queue-version.txt
lrwxrwxrwx 1 root   qscand        16 Jul 21 23:07 qscan -> /var/spool/qscan
drwxrwx— 5 qscand qscand      4096 Oct 12  2011 quarantine
-rw-r—– 1 root   qscand     12288 Jul 21 23:07 quarantine-events.db
-rw-r—– 1 qscand qscand     10443 Oct 12  2011 quarantine-events.txt
-rw-rw—- 1 qscand qscand    580033 Jul 21 23:07 quarantine.log
-rw-r—– 1 qscand qscand      2739 Oct 12  2011 settings_per_domain.txt
drwxr-x— 3 qscand qscand      4096 Jul 21 23:11 tmp
drwxrwx— 5 qscand qscand      4096 Oct 12  2011 working

 

Some suggested that /var/spool/qscan should be owned by qscand:clamav instead so I tried this but it didn't help,
others recommended adding clamav groupid into qscand's but this didn't help either:
 

root@ns2:/usr/local/src# grep -i clamav /etc/group
qscand:x:163:clamav,vpopmail
clamav:x:105:

 

Besides that I was getting also this shitty error:

 

Jul 21 20:05:42 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[ns2143750194279012466] clamdscan: corrupt or unknown clamd scanner error or memory/resource/perms problem – exit status -1/72057594037927935
Jul 21 20:06:51 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[ns2143750201179013125] clamdscan: corrupt or unknown clamd scanner error or memory/resource/perms problem – exit status -1/72057594037927935
Jul 21 20:15:42 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[ns214375025407906015] clamdscan: corrupt or unknown clamd scanner error or memory/resource/perms problem – exit status -1/72057594037927935
Jul 21 20:16:06 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[ns2143750256579011980] clamdscan: corrupt or unknown clamd scanner error or memory/resource/perms problem – exit status -1/72057594037927935
Jul 21 20:18:54 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[ns2143750273479014847] clamdscan: corrupt or unknown clamd scanner error or memory/resource/perms problem – exit status -1/72057594037927935
Jul 21 20:21:03 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[ns2143750286379028491] clamdscan: corrupt or unknown clamd scanner error or memory/resource/perms problem – exit status -1/72057594037927935
Jul 21 22:07:47 vps186637 qmail-scanner-queue.pl: X-Qmail-Scanner-2.08st:[ns2143750926779010097] clamdscan: corrupt or unknown clamd scanner error or memory/resource/perms problem – exit status 512/2

 

All the time in logs, so I thought something might be wrong with clamdscan and followed and tried some suggestions from qms1.net as described here, however none of the fixes described there worked for me …

I also tried to reinstall clamav from source using a bit of modified version of this tutorial

This didn't help either … I saw some suggestions online that the permission issues are caused by some wrong clamd.conf and freshclamd.conf configuration options – failing clamdscan, but this didn't work either. I also tried to remove clamdscan and substitute it with clamscan  as a suggested workaround but this didn't work either …

I spend about 6 hours trying to catch what is causing this issues so finally I went on and re-installed bigger part of Qmail using Thibs tutorial over the old installation.

I've also tried in mean time multiple time to rebuild qmail scanner database with:
 

setuidgid qscand /var/qmail/bin/qmail-scanner-queue.pl -g


Played around with permissions in /etc/clamav e.g.

 

 

chown -R qscand:clamav /var/log/clamav /var/lib/clamav /var/run/clamav
chown qscand:qscand /etc/clamav/freshclam.conf

 

 

 

Created:

/etc/cron.daily/qmail-scanner with following content

 

cat /etc/cron.daily/qmail-scanner
setuidgid qscand /var/qmail/bin/qmail-scanner-queue.pl -z


However in /var/log/qmail/qmail-smtpd/current and /var/log/qmail-send/current I continously got:

Qmail 451 qq temporary problem (#4.3.0) error

Interestingly during looking for a solution to the 451 qq temporary problem and:

status: qmail-todo stop processing asap / status: exiting – I've stumbled to my own blog post here 🙂

 

Finally, I tried to reinstall qmail-scanner and in mean time update it to  Version: 2.11 – st – patch – 20130319
Just to realized something was wrong with suidperl, e.g. in Debian 7.0.* Wheezy perl-suid binary is no longer in repositories so only way to have suidperl there is either to re-compile perl from source manually which is too much work and I think in most cases not worthy the effort or to use a small suid-wrapper:
 

#include <unistd.h>
#include <errno.h>
 

main( int argc, char ** argv, char ** envp )
{
              if( setgid(getegid()) ) perror( "setgid" );
              if( setuid(geteuid()) ) perror( "setuid" );
              envp = 0; /* blocks IFS attack on non-bash shells */
              system( "/usr/bin/perl", argv, envp );
              perror( argv[0] );
              return errno;
}

 


Create it into a file lets say suid-wrapperc and compile the file with GNU C Compiler:
 

$ gcc -o suid-wrapper suid-wrapper.c


Then move the suid-wrapper produced binary into /usr/bin/suidperl e.g.

 

 

$ mv suid-wrapper /usr/bin/suidperl


Last you will need to edit /var/qmail/bin/qmail-scanner-queue.pl

 

 

 

 

# vim /var/qmail/bin/qmail-scaner-queue.pl


And substitute

 

 

 

 

#!/usr/bin/perl -T


with:

 

 

#!/usr/bin/suidperl


Note!!! that qmail-scanner-queue.pl permissions should be suid and owned by qscand:qscand as follows:

 

 

 

 

ls -al /var/qmail/bin/qmail-scanner-queue.pl
-rwsr-sr-x 1 qscand qscand 159727 Jul 21 23:11 /var/qmail/bin/qmail-scanner-queue.pl


Finally to resolve the error I had to restart qmail via qmailctl start / stop script:

 

 

 

 

root@ns2:/var/qmail/bin# qmailctl restart
Restarting qmail:
* Stopping qmail-smtpdssl.
* Stopping qmail-smtpd.
* Sending qmail-send SIGTERM and restarting.
* Restarting qmail-smtpd.
* Restarting qmail-smtpdssl.

 

Finally to test emails are sent and receiver properly I used good old mail command part of bsd-mailx deb package

 

# mail -s "testing 12345678" testemail1234@gmail.com
asdfadf
.
Cc:

 

 

I've also tested with plain telnet to verify no errors because often the mail command doesn't return (show) errors on email sent and errors are written only in /var/log/mail.log or /var/log/qmail/* logs

 

 

# telnet localhost 25
Trying 127.0.0.1…
Connected to localhost.
Escape character is '^]'.
220 servername.localdomain.tld ESMTP
mail from: <testmail@test.com>
250 ok
rcpt to: <nospam@test.com>
250 ok
data
354 go ahead
From: Test_sender <testmail@test.com>
To: Test_receiver <nospam@test.com>
Subject: Just a stupid SMTP test

 

Just a test !
.
250 ok 1279384489 qp 3711
quit
221 servername.localdomain.tld
Connection closed by foreign host.

One other thing which probably helped I did was:

# qmailctl doqueue

 

Thanks God this time, it worked out without any QQ errors 🙂 !
 

 


Fixing Disappeared intel net link 5100 wifi on Toshiba Satellite L300 1YA

Friday, October 29th, 2010

Reading Time: 2 minutes

I've recently had to fix a Toshiba Satellite L300 1YA notebook , running the shitty Windows Vista operating system.
For some reason suddenly the Net Link 5100 Wi-FI Network Adapter of the laptop mysteriously disappeared.
The led indicating the device is enabled was blinking the driver showed properly installed in Windows -> System and everything.
Even though that the wireless network scanning in the notebook was not working.

In networking in System there were two lines showing up with excalammation mark "!".

To fix the mess it took me 3.5 hours. I tried many things first logical thing I tried was reinstalling the driver with the latest available from Intel's website. Anyways this doesn't helped so I was about to think about other solutions.
What made thinks even worse was that the Vista installed was in Chineese!, yes you red this correctly chineese. You cannot imagine what a hell it is to deal with Windows whose language pack was Chineese …

The Vista had installed also the Chineese antivirus program Rising which also provided the system with some weird firewall and this made the dealing with the problem even more complicated.

After many tries I finally completely removed the wireless driver on the system and reinstalled it with the latest version from Intel's website.
Thanksfully after a couple of reboots and going into save mode the Intel Net Link 5100 started working again by itself?!

Well you know how things goes with Windows, you never know what will happen next.

Maybe a lot of notebooks suffer the same weird issue with Wireless Wi-Fi adapter suddenly stopping to work.

So now you know the solution, remove the driver install it again, restart and it should be working again.
Hope this quick and dirty article will save somebody an hours of time to figure it out …


Ubuntu 9.04 Jaunty on Toshiba L300 PLSBGE Laptop

Sunday, September 20th, 2009

Reading Time: 2 minutes

toshiba-l300-plsbge-laptop-ubuntu-9.04-install

Today I had the task to Install Ubuntu GNU / Linux on Toshiba L300 PLSBGE Laptop.

I had already installed Windows Vista Enterprise on the notebook. Thus I used Acronis Disk Directory Suite to partition the harddrive for Ubuntu even though I could have used the gparted included on Ubuntu’s installation CD. I’ve asked specificly if
I could use the Ubuntu CD to repartition my hard drive in #ubuntu in irc.freenode.net.
The answer was positive it’s absolutely safe to resize an NTFS partition using Ubuntu’s installation LiveCD and gparted.That seems like a good news for all of us the free software users / enthusiasts / hobbyists etc.
I hated the default Ubuntu behaviour it automatically decided to install itself on a automatically created 2.5 GB partition.
I thought it won’t be so dumb to install itself on such a tiny partition. Well guess what I was wrong IT WAS SO DUMB!
Even though I had already 80 GB ext3 partition. Ubuntu’s default behaviour was to install on an automatically created 2.5GB partition.
Right after the installation I was stunned just to realize there was no free space on the drive where the dumbass installed itself.
After that I had some issues deleting the already cretead partitions, which for some reason messed up. Luckily the good old fdisk fixed the situation so I could easily delete all the partitions except the vista and recreate them again using gparted with Ubuntu’s install LiveCD. The install was completely flawless. Everything worked out of the box, no external efforts to fix broken stuff like usually happens in Linux fantastic! The only broken thing was that switching to plain console with ctrl+alt+f1 would visualize a non working display output and I couldn’t see the ttys at all. That wasn’t such a hassle since the system is planned to work only in GUI mode. I guess Ubuntu is going through a real development with a positive end results. Even external USB printer Canon PIXMA IP3300 worked by simply plugging it in. For some weird reason to make the printer work correctly I had to use driver for Canon PIXMA IP3000. Anyways it worked with it and the printer started printing correctly even though officially on some of the linux printers databases it’s reported the printer won’t work correctly never ever.END—–


Fix dosbox – setting: cycles=auto. If the game runs too fast try a fixed cycles amount in DOSBox’s options. Exit to error: DRC64:Unhandled memory reference

Thursday, October 12th, 2017

Reading Time: 2 minutes

fix-dosbox-error-setting-cycles-auto-game-runs-too-fast-exit-err-drc64-unhandled-memory-reference

I've recently installed Debian GNU / Linux 9.1 Stretch and on Ubuntu 16.10 Yakkety Yak and as an old school true gamer addict decided to play some games to recall the good old memories from the past of the glorious DOS games times, when all was simple people was real and there was no terrible people dividers such as Facebook  / GooglePlus, no skype fuzzy craziness and no people watching all time at their mobile smart phones like zoombies .

Well anyways, so I wanted to play my favourite DOS games Terminal Velocity, StarGunner, Raptor, Heroes of Might and Magic 2, Doom II, Duke 3d etc. etc. the list goes on and on – BTW What's your favourite old school DOS Game??

So I issues in Terminal:

$ dosbox TV.EXE

DOSBox version 0.74
Copyright 2002-2010 DOSBox Team, published under GNU GPL.

CONFIG:Loading primary settings from config file /home/zetathon/.dosbox/dosbox-0.74.conf
MIXER:Got different values from SDL: freq 44100, blocksize 512
ALSA:Can't subscribe to MIDI port (65:0) nor (17:0)
MIDI:Opened device:none
DOSBox switched to max cycles, because of the setting: cycles=auto. If    the game runs too fast try a fixed cycles amount in DOSBox's options.
Exit to error: DRC64:Unhandled memory reference

 

So what is the solution to  Exit to error: DRC64:Unhandled memory reference
error and why it happens?

Well, as the error clearly states the whole problem
comes from a default dosbox dos emulator configuration, that's the
setting:
 

cycles=auto


Perhaps the CPU beat of a Core I7 CPUs is too strong for some of the old games which are expecting a slower PC with less memory that's why the exception

Exit to Error: DRC64:Unhandled memory reference
is spit out by Dosemu.

So how to solve DRC64:Unhandled memory reference dosemu error?

By default DOSBOX places its configuration at  Linux / BSD / *nix-es at home folder /dosbox – e.g. ~/.dosbox/ the naming of dosbox.conf might differ according to dosbox version and the respective Linux / BSD distro, on Debian and Ubuntu Linux usually the naming includes a version number.

On Debian 9 Strecth Linux dosbox config is at ~/.dosbox/dosbox-0.74.conf

Edit the file
 

$ vim ~/.dosbox/dosbox-0.74.conf


and change inside the value for:

 

 

 

core=auto

to

core=normal

Then give dosbox with the erroring game another try, it worked for me
for me and everything seemed to run fine.

I've only run a handful of games but so far it seems to be working well.

If it does work but performance is degraded and tooks a huch hit on Gameplay you better try to substitute
 

core=normal

to
 

core=simple


AND HOORAY IT WORKS AGAIN! THE GAME RUN SUCCESSFULLY JOY TO THE WORLD! 🙂


How to enable Control Alt Backspace to Kill X server on Debian / Ubuntu Linux

Thursday, September 28th, 2017

Reading Time: 2 minutes

kill-X-server-switch-revert-back-to-ctrl-alt-backspace-howto
Being a long time GNU / Linux user, I've been quite dissatisfied for the fact that in latest Debian and Ubuntu Linux, the default Key combination to Kill X (CTRL + ALT + BACKSPACE) is no longer working.

Though nowdays Xorg (XServer) is pretty stable it still happens from time to time for some application to overload the PC badly and make Gnome or KDE environment little or no responsive at all and here comes the goody CTRL + ALT + BACKSPACE it is pretty much  like  (CTRL + ALT + DEL) did restarted the computer in DOS and earlier Windows OS-es once the environment became unusable with the only difference that just Xorg server is restarted and the other using programs that are in background work just like they used to. 

CTRL + ALT + Backspace is a great thing to use especially if you're running some homebrew server and you use it both as a Server with some few little websites and as a Desktop environment to browse the net and do basic stuff.

So here comes the question how to make the CTRL + ALT + BACKSPACE keyboard combination be killing Xserver like in the good old days?

The easiest way to do it interactively in ncurses interface is by  running:

 

root@noah:~# dpkg-reconfigure keyboard-configuration

 

If somehow on the machine you don't have dpkg-reconfigure or you prefer to do set CTRL + ALT + BACKSPACE Kill Switch manually edit /etc/default/keyboard 

inside change value of

 

XKBOPTIONS="terminate:ctrl_alt_bksp" 

 

like shown below file:

root@noah:/home/hipo# cat  /etc/default/keyboard

# KEYBOARD CONFIGURATION FILE

# Consult the keyboard(5) manual page.

XKBMODEL="pc105"
XKBLAYOUT="us"
XKBVARIANT=""
XKBOPTIONS="terminate:ctrl_alt_bksp"

BACKSPACE="guess"

The configuration should be working across Debian 7, 8, 9 as well as Ubuntu 12 ..14 .. 16 and hopefully in future releases too, just as many other Linux distributions like Mint etc. the Xserver Kill Switch setting should be located in same file.

Finally if even after that change the Control Alt BackSpace Kill Switch sequence refuses to work in GNOME Desktop environment, it might be due to a local setting typical for GNOME and this should be fixed via the good known gnome-tweak-tool

So GNOME users should run it from command line and check the setting there, e.g.:

 

$ gnome-tweak-tool


You should check:


 

Typing -> Kill Sequence to Kill the X Server

 


it should look like shown in below screenshot:

how-to-set-X-server-kill-switch-in-GNOME-gnak-tool-screenshot-debian-stretch