Walking in Light With Christ - hip0's personal blog on System Administration, Free Software, Computer Security and Religion

After finding out How PC Speaker is muted on Linux , I've decided to also disable the annoying beeps on BSD. This is in tandem with the minimalistic philosophy I try to apply to every server I manage.

Also on BSD Desktop machines it is quite annoying especially if csh (C Shell) is used, everytime you press TAB you get the beep sound. On BSD beep sound produced on tab completion is louder than in Linux and that makes it even more annoying ...

Disabling pc-speaker beeps on BSDs is done via a sysctl kernel variable:

freebsd# sysctl hw.syscons.bell=0 hw.syscons.bell: 0 -> 0


To further permanently disable on system boot add hw.syscons.bell=0 to /etc/sysctl.conf, e.g.:

freebsd# echo 'hw.syscons.bell=0' >> /etc/sysctl.conf


Why would anyone disable ACPI support on a server machine, well simple ACPI loaded code is just another piece of code constantly loaded in the memory on kernel boot up - that can produce a fatal bug leading to a system crash (kernel panic).

Many computers ship with buggy or out of specifications ACPI firmware which can cause a severe oddities on a brand new bought piece of irons.
One such oddity that can be related to ACPI motherboard support problems is if you notice your machine randomly powering off or failing to boot with a brand new Linux installed on it.
Another reason is the ACPI code will let the kernel control the CPU fan on a softwre level and on high CPU heat up it will instruct the fan to rotate quickly and on low system loads it will bring back the fan to loose speed.
If this switch of FAN from high speed to low speed has to be done too frequently this increases the probability for a short fan damage and possible system outage due to overheats.

Therefore I recommend the ACPI support is switched off completely on all servers, where it no specifically needed for CPU heat temperature tracking with lm_sensors or any piece of hardwre vendor specific software provided.

There are 3 ways to disable fully or partially ACPI support.


- One is to disable it straight for BIOS (best way IMHO)
- Disable via GRUB or LILO passing a kernel parameter
- Partial ACPI off-ing - /disabling the software that controls the CPU fan/


1. Disable ACPI in BIOS level

Press DEL, F1, F2, F10 or whatever the enter bios key combination is go through all the different menus (depending on the vios BENDOR) and make sure every occurance of ACPI is set to off / disable whatever it is called.

Below is a screenshot of menus with ACPI stuff on a motherboard equipped with Phoenix AwardBIOS:



This is the best and safest way to disable ACPI power saving, unfortunately some newer PCs lack the functionality to disable ACPI; (probably due to the crazy "green" policy the whole world is nowdays crazy about).
If that's the case with you, thanksfully there is a "software way" to disable ACPI via passing kernel options via GRUB and LILO boot loaders.

2. Disabling ACPI support on kernel boot level through GRUB boot loader config

There is a tiny difference command to pass for ACPI disabling between GRUB ver. 1.x and GRUB 2.x.

a) In GRUB 0.99 (GRUB version 1)

Edit file /etc/grub/menu.lst or /etc/grub/grub.conf (location differs across Linux distriubution), therein append:

acpi=off


to the end of kernel command line.

Here is an example of a kernel command line with ACPI not disabled (example taken from CentOS server grub.conf):

[root@centos ~]# grep -i title -A 4 /etc/grub/grub.conf
title Red Hat Enterprise Linux Server (2.6.18-36.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-36.el5 ro root=/dev/VolGroup00/LogVol00 console=ttyS0,115200n8
initrd /initrd-2.6.18-36.el5.img


The editted version of the file with acpi=off included should look like so:

title Red Hat Enterprise Linux Server (2.6.18-36.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-36.el5 ro root=/dev/VolGroup00/LogVol00 console=ttyS0,115200n8 acpi=off
initrd /initrd-2.6.18-36.el5.img


The root=/dev/VolGroup00/LogVol00 means the the server is configured to use LVM (Logical Volume Manager).

b) Disabling ACPI on GRUB version 1.99 +

This version is by default installed on newer Ubuntu and Debian Linux.

In grub 1.99 on latest Debian Squeeze, the file to edit is located in /boot/grub/grub.cfgthe file is more messy than with its predecessor menu.lst (grub 0.99). Thanksfully there is no need to directly edit the file (though this is possible), but on newer Linuxes usually there is another simplied grub config file /etc/grub/config

Hence to add the acpi=off to 1.99 open /etc/grub/config find the line reading:

GRUB_CMDLINE_LINUX_DEFAULT="quiet"


and append the "acpi=off" option, e.g. the line has to change to:

GRUB_CMDLINE_LINUX_DEFAULT="quiet acpi=off"


On some servers it might be better to also disable APIC along with ACPI:

Just in case you don't know what is the difference between ACPI and APIC, here is a short explanation:

ACPI = Advanced Configuration and Power Interface


APIC = Advanced Programmable Interrupt Controllers

ACPI is the system that controls your dynamic speed fans, the power button behavior, sleep states, etc.

APIC is the replacement for the old PIC chip that used to come imbedded on motherboards that allowed you to setup interrupts for your soundcard, ide controllers, etc.
Hence on some machines experiencing still problems with even ACPI switched off it might be a wise idea to disable the APIC support too, by passing instead to the kernel:

acpi=off noapic noacpi


Anyways, while doing the changes, be very very cautious or you might end up with unbootable server, don't blame me if this happens :); Be sure you have a backup option if server doesn't boot.
I remember GRUB has ability to be configured to automatically load up a second kernel if 1st one fails to boot so I guess this could be a wise thing to investigate if you have to be 100% sure the system will boot fine after grub changes.
To load up the kernel with the new setting, give it a restart:

[root@centos ~]# shutdown -r now
....


3. Disable ACPI support on kernel boot time on Slackwares or other Linuxes still booting with LILO

Still, some Linux distros like Slackware, decided to keep the old way and use LILO (Linux Loader) as a default boot loader.

Disabling ACPI support in LILO is done through /etc/lilo.conf
By default in /etc/lilo.conf, there is a line:

append= acpi=on


it should be changed with:

append= acpi=off


Next to load up the new acpi disabled setting, lilo has to be reloaded:

slackware:~# /sbin/lilo -c /etc/lilo.conf
....

br /> Finally a reboot is required (if you don't have a physical access or someone near the server you better not )

slackware:~# reboot
....


4. Disable ACPI fan control support on a running Linux server without restart

This is the most secure work-around, to disabling the ACPI control over the machine CPU fan, however it has a downside that still the ACPI code will be loaded in the kernel and could cause kernel issues possibly in the long run.

The acpid support on Linux is controlled by acpid or haldaemon (depending on the Linux distro), hence to disable the fan control on servers this services has to be switched off:

a) disabling ACPI on Debian and deb based Linuces As of time of writting on Debian Linux servers acpid (Advanced Configuration and Power Interface event daemon) is there to control how power management will be handled. To disable it stop it as a service (if running):

debian:~# /etc/init.d/acpid stop


To permanently remove acpid from boot up on system boot disable it with update-rc.d:

debian:~# update-rc.d acpid disable 2 3 4 5
update-rc.d: using dependency based boot sequencing
insserv: Script iptables is broken: incomplete LSB comment.
insserv: missing `Required-Start:' entry: please add even if empty.
insserv: warning: current start runlevel(s) (empty) of script `acpid' overwrites defaults (2 3 4 5).
insserv: warning: current stop runlevel(s) (2 3 4 5) of script `acpid' overwrites defaults (empty).
insserv: missing `Required-Start:' entry: please add even if empty.


b) disabling ACPI on RHEL, Fedora and other Redhats

I'm not sure if this is safe,as many newer redhat servers might not work properly with haldaemon disabled.
Well anyways you can give it a try if when it is stopped there are issues just bring it up.
[root@rhel ~]# /etc/init.d/haldaemon stop


If all is fine with the haldaemon switched off (hope so), you can completely disable it to load on start up with:

[root@centos ~]# /sbin/chkconfig --level 2 3 4 5 haldaemon off


A friend of mine bring home a Seagate External Hard Disk Drive using USB 3 as a communication media. I needed to attach the hard disk to my FreeBSD router to transfer him some data, the External HDD is formatted to use NTFS as a main file partition and hence to make the file transfers I had to somehow mount the NTFS partition on the HDD.

FreeBSD and other BSDs, just like Linux does not have embedded NTFS file system mount support.
In order to add an external write support for the plugged hdd NTFS I looked in the ports tree:

freebsd# cd /usr/ports
freebsd# make search name='ntfs'
Port: fusefs-ntfs-2010.10.2
Path: /usr/ports/sysutils/fusefs-ntfs
Info: Mount NTFS partitions (read/write) and disk images
Maint: ports@FreeBSD.org
B-deps: fusefs-libs-2.7.4 libiconv-1.13.1_1 libtool-2.4 libublio-20070103 pkg-config-0.25_1
R-deps: fusefs-kmod-0.3.9.p1.20080208_7 fusefs-libs-2.7.4 libiconv-1.13.1_1 libublio-20070103 pkg-config-0.25_1
WWW: http://www.tuxera.com/community/

Port: ntfsprogs-2.0.0_1
Path: /usr/ports/sysutils/ntfsprogs
Info: Utilities and library to manipulate NTFS partitions
Maint: ports@FreeBSD.org
B-deps: fusefs-libs-2.7.4 libiconv-1.13.1_1 libublio-20070103 pkg-config-0.25_1
R-deps: libublio-20070103 pkg-config-0.25_1
WWW: http://www.linux-ntfs.org/
freebs# cd sysutils/fusefs-ntfs/
freebsd# ls
Makefile distinfo files/ pkg-descr pkg-plist
freebsd# cat pkg-descr
The ntfs-3g driver is an open source, freely available read/write NTFS
driver, which provides safe and fast handling of the Windows XP, Windows
Server 2003 and Windows 2000 filesystems. Almost the full POSIX filesystem
functionality is supported, the major exceptions are changing the file
ownerships and the access rights.
WWW: http://www.tuxera.com/community/



Using ntfs-3g I managed to succeed mounting the NTFS on my old PC running FreeBSD ver. 7_2

1. Installing fuserfs-ntfs support on BSD

Before I can use ntfs-3g, to mount the paritition, I had to install fuserfs-ntfs bsd port, with:

freebsd# cd /usr/ports/sysutils/fusefs-ntfs
freebsd# make install clean
.....


I was curious if ntfsprogs provides other utilities to do the ntfs mount but whilst trying to install it I realized it is already installed as a dependency package to fusefs-ntfs.

fusefs-ntfs package provides a number of utilities for creating, mounting, fixing and doing various manipulations with Microsoft NTFS filesystems.

Here is a list of all the executable utilities helpful in NTFS fs management:

freebsd# pkg_info -L fusefs-ntfs\* | grep -E "/bin/|/sbin|README"
/usr/local/bin/lowntfs-3g
/usr/local/bin/ntfs-3g
/usr/local/bin/ntfs-3g.probe
/usr/local/bin/ntfs-3g.secaudit
/usr/local/bin/ntfs-3g.usermap
/usr/local/bin/ntfscat
/usr/local/bin/ntfscluster
/usr/local/bin/ntfscmp
/usr/local/bin/ntfsfix
/usr/local/bin/ntfsinfo
/usr/local/bin/ntfsls
/usr/local/sbin/mkntfs
/usr/local/sbin/ntfsclone
/usr/local/sbin/ntfscp
/usr/local/sbin/ntfslabel
/usr/local/sbin/ntfsresize
/usr/local/sbin/ntfsundelete
/usr/local/share/doc/ntfs-3g/README
/usr/local/share/doc/ntfs-3g/README.FreeBSD


The README and README.FreeBSD are wonderful, reading for those who want to get more in depth knowledge on using the up-listed utilities.

One utility, worthy to mention, I have used in the past is ntfsfix. ntfsfix resolve issues with NTFS partitions which were not unmounted on system shutdown (electricity outage), system hang up etc.

2. Start fusefs (ntfs) and configure it to auto load on system boot

Once fuserfs-ntfs is installed, if its necessery ntfs fs mounts to be permanently supported on the BSD system add fusefs_enable="YES" to /etc/rc.conf - (the FreeBSD services auto load conf).

freebsd# echo 'fusefs_enable="YES"' >> /etc/rc.conf


One note to make here is that you need to have also dbus_enable="YES" and hald_enable="YES" in /etc/rc.conf, not having this two in rc.conf will prevent fusefs to start properly. Do a quick grep to make sure this two variables are enabled:

Afterwards fsusefs load up script should be run:

freebsd# /usr/local/etc/rc.d/fusefs start
Starting fusefs.


Another alternative way to load ntfs support on the BSD host is to directly load fuse.ko kernel module:

freebsd# /sbin/kldload fuse.ko


3. Mounting the NTFS partition

In my case, the Seagate hard drive was detected as da0, where the NTFS partition was detected as s1 (da0s1):

freebsd# dmesg|grep -i da0
da0 at umass-sim0 bus 0 target 0 lun 0
da0: Fixed Direct Access SCSI-4 device
da0: 40.000MB/s transfers
da0: 953869MB (1953525164 512 byte sectors: 255H 63S/T 121601C)br /> GEOM_LABEL: Label for provider da0s1 is ntfs/Expansion Drive.
GEOM_LABEL: Label for provider da0s1 is ntfs/Expansion Drive.


Therefore further to mount it one can use mount_ntfs (to quickly mount in read only mode) or ntfs-3g for (read / write mode):

If you need to just quickly mount a disk drive to copy some data and umount it with no need for writting to the NTFS partition do;

freebsd# /sbin/mount_ntfs /dev/ad0s1 /mnt/disk


Note that mount_ntfs command is a native BSD command and have nothing to do with ntfs-3g. Therefore using it to mount NTFS is not the same as mounting it via ntfs-3g cmd

freebsd# /usr/local/bin/ntfs-3g -o rw /dev/da0s1 /mnt/disk/


Something, I've noticed while using ntfs-3g is, it fails to properly exit even when the ntfs-3g shell execution is over:

freebsd# ps ax |grep -i ntfs|grep -v grep
18892 ?? Is 0:00.00 /usr/local/bin/ntfs-3g -o rw /dev/da0s1 /mnt/disk/


I dunno if this is some kind of ntfs-3g bug or feature specific to all versions of FreeBSD or it is something local to FBSD 7.2

Thought ntfs-3g, keeps appearing in process list, praise God as of time of writting NTFS support on FreeBSD prooved to be stable.
Read / Write disk operations to the NTFS I tested it with works great. Just about 5 years ago I still remember write mode was still experimental. Now it seems NTFS mounts can be used with no hassle even on production machines.

4. Auto mounting NTFS partition on FreeBSD system boot

There are two approaches towards 'the problem' I can think of.
The better way to auto mount on boot (in my view) is through /etc/fstab use

If /etc/fstab + ntfs-3g is to be used, you will however change the default /sbin/mount_ntfs command to point to /usr/local/bin/ntfs-3g, i.e.:

freebsd# mv /sbin/mount_ntfs /sbin/mount_ntfs.orig
freebsd# ln -s /usr/local/bin/ntfs-3g /sbin/mount_ntfs


Then to mount /dev/da0s1 via /etc/fstab add line:

/dev/ad0s1 /mnt/disk ntfs rw,late 0 0


To not bother with text editor run:

freebsd# echo '/dev/ad0s1 /mnt/disk ntfs rw,late 0 0' >> /etc/fstab


I've red in posts in freebsd forums, there is also a way to use ntfs-3g for mounting partitions, without substituting the original bsd /sbin/mount_ntfs, the exact commands suggested to be used with no need to prior mv /sbin/mount_ntfs to /sbin/mount_ntfs.orig and link it to ntfs is:

/dev/ad0s1 /disk ntfs rw,mountprog=/usr/local/bin/ntfs-3g,late 0 0


For any other NTFS partitions, for instance /dev/ad0s2, /dev/ad2s1 etc. simply change the parititon name and mount points.

The second alternative to adding the NTFS to auto mount is through /etc/rc.local. /etc/rc.local content will be executed very late in system boot. :

echo '/usr/local/bin/ntfs-3g -o rw /dev/da0s1' >> /etc/rc.local


One disadvanage of using /etc/rc.local for mounting the partition is the hanging ntfs-3g in proc list:

freebsd# ps ax |grep -i ntfs|grep -v grep
18892 ?? Is 0:00.00 /usr/local/bin/ntfs-3g -o rw /dev/da0s1 /mnt/disk/


Though, I haven't tested it yet. Using the same methodology should be perfectly working on PC-BSD, DragonFlyBSD, NetBSD and OpenBSD.
I will be glad if someone who runs any of the other BSDs can confirm, following this instructions works fine on these BSDs too.

If you're a Linux server administrator running MySQL server, you need to troubleshoot performance and bottleneck issues with the SQL database every now and then. In this article, I will pinpoint few methods to debug basic issues with MySQL database servers.

1. Troubleshooting MySQL database queries with native SQL commands

a)One way to debug errors and get general statistics is by logging in with mysql cli and check the mysql server status:

# mysql -u root -p
mysql> SHOW STATUS;
+-----------------------------------+------------+
| Variable_name | Value |
+-----------------------------------+------------+
| Aborted_clients | 1132 |
| Aborted_connects | 58 |
| Binlog_cache_disk_use | 185 |
| Binlog_cache_use | 2542 |
| Bytes_received | 115 |
.....
.....
| Com_xa_start | 0 |
| Compression | OFF |
| Connections | 150000 |
| Created_tmp_disk_tables | 0 |
| Created_tmp_files | 221 |
| Created_tmp_tables | 1 |
| Delayed_errors | 0 |
| Delayed_insert_threads | 0 |
| Delayed_writes | 0 |
| Flush_commands | 1 |
.....
.....
| Handler_write | 132 |
| Innodb_page_size | 16384 |
| Innodb_pages_created | 6204 |
| Innodb_pages_read | 8859 |
| Innodb_pages_written | 21931 |
.....
.....
| Slave_running | OFF |
| Slow_launch_threads | 0 |
| Slow_queries | 0 |
| Sort_merge_passes | 0 |
| Sort_range | 0 |
| Sort_rows | 0 |
| Sort_scan | 0 |
| Table_locks_immediate | 4065218 |
| Table_locks_waited | 196 |
| Tc_log_max_pages_used | 0 |
| Tc_log_page_size | 0 |
| Tc_log_page_waits | 0 |
| Threads_cached | 51 |
| Threads_connected | 1 |
| Threads_created | 52 |
| Threads_running | 1 |
| Uptime | 334856 |
+-----------------------------------+------------+
225 rows in set (0.00 sec)


SHOW STATUS; command gives plenty of useful info, however it is not showing the exact list of queries currently processed by the SQL server. Therefore sometimes it is exactly a stucked (slow queries) execution, you need to debug in order to fix a lagging SQL. One way to track this slow queries is via enabling mysql slow-query.log. Anyways enabling the slow-query requires a MySQL server restart and some critical productive database servers are not so easy to restart and the SQL slow queries have to be tracked "on the fly" so to say.
Therefore, to check the exact (slow) queries processed by the SQL server (without restarting it), do

mysql> SHOW processlist;
+------+------+---------------+------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+------+------+---------------+------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
| 609 | root | localhost | blog | Sleep | 5 | | NULL |
| 1258 | root | localhost | NULL | Sleep | 85 | | NULL |
| 1308 | root | localhost | NULL | Query | 0 | NULL | show processlist |
| 1310 | blog | pcfreak:64033 | blog | Query | 0 | Sending data | SELECT comment_author, comment_author_url, comment_content, comment_post_ID, comment_ID, comment_aut |
+------+------+---------------+------+---------+------+--------------+------------------------------------------------------------------------------------------------------+
4 rows in set (0.00 sec)
mysql>


SHOW processlist gives a good view on what is happening inside the SQL.

To get more complete information on SQL query threads use the full extra option:

mysql> SHOW full processlist;


This gives pretty full info on running threads, but unfortunately it is annoying to re-run the command again and again - constantly to press UP Arrow + Enter keys.

Hence it is useful to get the same command output, refresh periodically every few seconds. This is possible by running it through the watch command:

debian:~# watch "'show processlist' | mysql -u root -p'secret_password'"


watch will run SHOW processlist every 2 secs (this is default watch refresh time, for other timing use watch -n 1, watch -n 10 etc. etc.

The produced output will be similar to:

Every 2.0s: echo 'show processlist' | mysql -u root -p'secret_password' Thu May 10 17:24:19 2012

Id User Host db Command Time State Info
609 root localhost blog Sleep 3 NULL 1258 root localhost NULL Sleep 649 NULL 1542 blog pcfreak:64981 blog Query 0 Copying to tmp table \
SELECT p.ID, p.post_title, p.post_content,p.post_excerpt, p.pos
t_date, p.comment_count, count(t_r.o
1543 root localhost NULL Query 0 NULL show processlist


Though this "hack" is one of the possible ways to get some interactivity on what is happening inside SQL server databases and tables table. for administering hundred or thousand SQL servers running dozens of queries per second - monitor their behaviour few times aday using mytop or mtop is times easier.

Though, the names of the two tools are quite similar and I used to think both tools are one and the same, actually they're not but both are suitable for monitoring sql database execution in real time.

As a sys admin, I've used mytop and mtop, on almost each Linux server with MySQL server installed.
Both tools has helped me many times in debugging oddities with sql servers. Therefore my personal view is mytop and mtop should be along with the Linux sysadmin most useful command tools outfit, still I'm sure many administrators still haven't heard about this nice goodies.

1. Installing mytop on Debian, Ubuntu and other deb based GNU / Linux-es

mytop is available for easy install on Debian and across all debian / ubuntu and deb derivative distributions via apt.

Here is info obtained with apt-cache show

debian:~# apt-cache show mytop|grep -i description -A 3
Description: top like query monitor for MySQL
Mytop is a console-based tool for monitoring queries and the performance
of MySQL. It supports version 3.22.x, 3.23.x, 4.x and 5.x servers.
It's written in Perl and support connections using TCP/IP and UNIX sockets.


Installing the tool is done with the trivial:

debian:~# apt-get --yes install mytop
....


mtop used to be available for apt-get-ting in Debian Lenny and prior Debian releases but in Squeeze onwards, only mytop is included (probably due to some licensing incompitabilities with mtop??).

For those curious on how mtop / mytop works - both are perl scripts written to periodically connects to the SQL server and run commands similar to SHOW FULL PROCESSLIST;. Then, the output is parsed and displayed to the user.

Here how mytop running, looks like:



2. Installing mytop on RHEL and CentOS

By default in RHEL and CentOS and probably other RedHat based Linux-es, there is neither mtop nor mytop available in package repositories. Hence installing the tools on those is only available from 3rd parties. As of time of writting an rpm builds for RHEL and CentOS, as well as (universal rpm distros) src.rpm package is available on http://pkgs.repoforge.org/mytop/. For the sake of preservation - if in future those RPMs disappear, I made a mirror of mytop rpm's here

Mytop rpm builds depend on a package perl(Term::ReadKey), my attempt to install it on CentOS 5.6, returned following err:

[root@cenots ~]# rpm -ivh mytop-1.4-2.el5.rf.noarch.rpm
warning: mytop-1.4-2.el5.rf.noarch.rpm: Header V3 DSA signature: NOKEY, key ID 6b8d79e6
error: Failed dependencies:
perl(Term::ReadKey) is needed by mytop-1.4-2.el5.rf.noarch


The perl(Term::ReadKey package is not available in CentOS 5.6 and (probably other centos releases default repositories so I had to google perl(Term::ReadKey) I found it on http://rpm.pbone.net/ package repository, the exact url to the rpm dependency as of time of writting this post is:

ftp://ftp.pbone.net/mirror/yum.trixbox.org/centos/5/old/perl-Term-ReadKey-2.30-2.rf.i386.rpm

Quickest, way to install it is:

[root@centos ~]# rpm -ivh ftp://ftp.pbone.net/mirror/yum.trixbox.org/centos/5/old/perl-Term-ReadKey-2.30-2.rf.i386.rpm Retrieving ftp://ftp.pbone.net/mirror/yum.trixbox.org/centos/5/old/perl-Term-ReadKey-2.30-2.rf.i386.rpm Preparing... ########################################### [100%]
1:perl-Term-ReadKey ########################################### [100%]


This time mytop, install went fine:

[root@centos ~]# rpm -ivh mytop-1.4-2.el5.rf.noarch.rpm
warning: mytop-1.4-2.el5.rf.noarch.rpm: Header V3 DSA signature: NOKEY, key ID 6b8d79e6
Preparing... ########################################### [100%]
1:mytop ########################################### [100%]


To use it further, it is the usual syntax:

mytop -u username -p 'secret_password' -d database




3. Installing mytop and mtop on FreeBSD and other BSDs

To debug the running SQL queries in a MySQL server running on FreeBSD, one could use both mytop and mtop - both are installable via ports:

a) To install mtop exec:

freebsd# cd /usr/ports/sysutils/mtop
freebsd# make install clean
....


b) To install mytop exec:

freebsd# cd /usr/ports/databases/mytop
freebsd# make install clean
....


I personally prefer to use mtop on FreeBSD, because once run it runs prompts the user to interactively type in the user/pass

freebsd# mtop


Then mtop prompts the user with "interactive" dialog screen to type in user and pass:



It is pretty annoying, same mtop like syntax don't show user/pass prompt:

freebsd# mytop
Cannot connect to MySQL server. Please check the:

* database you specified "test" (default is "test")
* username you specified "root" (default is "root")
* password you specified "" (default is "")
* hostname you specified "localhost" (default is "localhost")
* port you specified "3306" (default is 3306)
* socket you specified "" (default is "")
The options my be specified on the command-line or in a ~/.mytop
config file. See the manual (perldoc mytop) for details.
Here's the exact error from DBI. It might help you debug:
Unknown database 'test'


The correct syntax to run mytop instead is:

freebsd# mytop -u root -p 'secret_password' -d 'blog'


Or the longer more descriptive:

freebsd# mytop --user root --pass 'secret_password' --database 'blog'


By the way if you take a look at mytop's manual you will notice a tiny error in documentation, where the three options --user, --pass and --database are wrongly said to be used as -user, -pass, -database:

freebsd# mytop -user root -pass 'secret_password' -database 'blog'
Cannot connect to MySQL server. Please check the:

* database you specified "atabase" (default is "test")
* username you specified "ser" (default is "root")
* password you specified "ass" (default is "")
* hostname you specified "localhost" (default is "localhost")
* port you specified "3306" (default is 3306)
* socket you specified "" (default is "")a
...
Access denied for user 'ser'@'localhost' (using password: YES)


Actually it is interesting mytop, precededed historically mtop.
mtop was later written (probably based on mytop), to run on FreeBSD OS by a famous MySQL (IT) spec -- Jeremy Zawodny .
Anyone who has to do frequent MySQL administration tasks, should already heard Zawodny's name.
For those who haven't, Jeremy used to be a head database administrators and developer in Yahoo! Inc. some few years ago.
His website contains plenty of interesting thoughts and writtings on MySQL server and database management

I never liked Mandrake Linux, since day 1 I saw it.
Historically Mandrake Linux was one of the best Linux distributions available for free download in the "Linux scene" some 10 to 12 years ago.

Mandrake was simple gui oriented and trendy. It also one the Linux distribution with the most simplified installer program and generally a lot of GUI software for easy configuration and use by the end user.

Though it's outside nice look, still for me it was like an "intuition" that Mandrake is not so good as it appeared.

Now many years later I found by chance that Mandrake has been sued to change their Operating System name with another, due to a law suit requit by the copyright holders of Mandrake The Magician comics. "Mandrake the Magician" used to be a very popular before the Second World war in the 1930's.



It obviously not a co-incidence that the Mandrake names was after this comics and not the mandrake herb plants available in Europe, Africa and Asia. This is clear in Mandrake Linux distro earlier mascot, you see below:



Later on they changed Mandrake's logo to loose the connection with Mandrake The Magician and used another new crafted logo:


Its quite stunning nowdays magician obsession, has so heavily infiltrated our lives that even something like a Free Softwre Linux distribution might have some kind of reference to magician and occult stuff (I saw this from the position of being Christian) ...

Later due to the name copyright infringement Mandrake Linux was renamed first to Mandragora Linux.
Instead of putting some nice name non related to occultism or magic stuff the French commercian company behind Mandrake rename it to another non-Christian name Mandragora.
Interestingly the newer name Mandragora as one can read in wikipedia means:

Mandragora (demon), in occultism

Well apparently, someone from the head developers of this Linux distribution has a severe obsession with magic and occultism.

Later MandrakeSoft (The French Company behind Mandrake Linux) renamed finally the distribution to Mandriva under the influence of the merger of Mandrake with the Brazillian company Connectiva this put also an over to the legal dispute copyright infringement dispute with Hearst Corporation (owning the rights of Mandrake the Magician).

Having in mind all fact on current Mandriva "dark names history", I think it is better we Christians avoid it ...

I'm starting to learn some video editting, as I need it sometimes for building client websites.
As a Linux user I needed to have some kind of software for amateur video editting. For Microsoft Windows OS, there are tons of video editor programs both free and proprietary (paid).
Windows users can for instance use the free software program VirtualDub (licensed under GPL license) to easily cut movie scenes from a video.

Unfortunately VirtualDub didn't have a Linux or BSD version so in my case I had to look for another soft.


I consulted a friend of mine who recommended a video editor program called LiVES.

If you haven't done any video editting previously on Linux (like my case was), you will certainly be happy to try LiVES



LiVES can extract only sound from videos, cut selected parts (frames) from videos and do plenty of other nice stuff. It is just great piece of software for anyone, who needs to do simply (newbie) video editting.

With LiVES even an amateur video editor like me could, immediately learn how to chop a movie scenes ...




To master the basics and edit one video in FLV format it took me about 1 hour of time, as in the beginning it was confusing to get confortable with the program scenes selector.

One downside of LiVES it failure to open a FLV file I wanted to edit.
In order to be able to edit the flv movie hence I first had to convert the FLV to AVI or MPEG, as this two (video multimedia formats) are supported by LiVES video editor.

After completing my video scenes chopping to the AVI file I had to convert back to FLV.

In order to complete the convertion between FLV to AVI format on my Debian Linux, I used a program called avidemux

Avidemux has a nice GUI interface and also like Lives has support for video editting, though I have never succesfully done any video edits with it.

Avidemux IMHO is user (completely intuitive). To convert the FLV to AVI, all I had to do was simply open the file FLV file, press (CTRL+S) select my FLV video file format and select the output file extension format to be AVI.

Further on, used LiVES to cut my desired parts from my video of choice. Once the cuts were complete I saved the new cutted version of video to AVI.
Then I needed the video again in FLV to upload it in Joomla, so used ffmpeg - command line tool to do the AVI to FLV file converstion, like so:

hipo@noah:~$ /usr/bin/ffmpeg -i my_media_file.avi my_video_file.flv


Hope this article helps someone aiming to do basic video editting on Linux with LiVES and just like needed FLV to AVI and AVI to FLV convertions.

I believe, the quickest way to take notes on Linux and BSD and later view the notes is to use the command line.
A very easy simple way to keep record of various short notes is just to use a simple text editor like (vim) and store each note in a separate file in lets say ~/notes/ directory.
Actually, I'm using this way to take notes and store sensitive info for various important information I need for further reference, since 5 years or so..
Opening a new text editor for each note and then doing cd ~/notes/; ls |grep -i 'string' is a bit time consuming.
Fortunately there is a quick two shell functions hack that shortens time for note taking. The following two bash functions has to be added in ~/.bashrc:

n() {
vim ~/notes/"$*".txt
}
nls() {
ls {
ls -c ~/notes/ | grep "$*"
}


Copy / Paste this two functions in the beginning or the end of ~/.bashrc in order to use them.

Also if ~/notes directory is not existing, yet create it:

hipo@noah:~$ mkdir notes


To make the two new input functions active across opened bash shells on console or terminal either re-login or reread the .bashrc by "sourcing it", e.g.

hipo@noah:~$ source ~/.bashrc


Afterwards, note taking becomes a piece of cake to store a new note with login credentials (user/password) for a new registration to a random named website, type something like:

hipo@noah:~$ n my_website_name-user-pass


This will open for editting ~/.notes/my_website_name-user-pass.txt, type the new desired note content and do save and exit from vim (press esc and type :x!.

Then to get a quick list of all previously stored notes use:

hipo@noah:~$ nls website
my_website_name-user-pass.txt


If you already have a directory containing subdirectories with various taken notes (like me), you will need to use an improved version nls written by Jason Ryan, the nls improved is like this:

nls () { tree -CR --noreport ~/notes | awk '{
if ((NR >) gsub(/.txt/,"")); if
(NF==1) print $1; else if (NF==2)
print $2; else if (NF==3)
printf " %s\n", $3}';
}


This two functions, were not my creation but was suggested in Linux Magazine issue 135 article entitled Command-line task managers and note-taking tools written by Dmitri Popov.

Hope this two functions, will be helpful to console geeks out there.

Lately, I'm starting to use my tty consoles more and more. Most of the people should be probably aware of the existence of lynx, elinks and w3m enabling the text geek to browse or debug web pages in plain text mode.
Anyhow, for people who did not used one of the aforementioned browsers to text brose the net I warmly suggest you give them a try. For install and short description on 'em see my previous post - Text mode console browsing with lynx, elinks, w3m and links text browsers ...

For people dedicated to only use console and text mode console on their Personal Computer, simply installing and using this text browsers will not allow you to view any images tags in the html.
Nowdays one of the reasons many people would decide not to use console is simply they want to see pictures, hence I believe by having the opportunity to have almost fully functional text browsing in cosnole / or terminal many might choose not to bother with heavy resource consuming desktop browsers (Firefox, Google Chrome, Opera etc.).

A good reason why you might want to use a console browser instead of its Desktop "big brother" would be simply efficiency. Console and keyboard access to commands is always faster!

Besides that, I'm convinced there are many hard core geeks out there, who still can happily live without Macromedia Flash ads and Videos, but can't simply drop off browser image viewing and switch to lynx, for this group of users having support for graphical browsing in console is also a must.

Hence many people who doesn't have a specific requirement for GUI programs but still use (mutt, ssh, vim, mpg321, zgv etc.) to do most of their work in text console, use X windows in conjunction with mimalistic graphical environment like (DropBox, XFCE ...) for the only reason to be able viewing the pictures embedded in web pages.

With all above said, as me is being a guy keen on console tty browsing, while checking the available console browsers few days ago, I've stumbled on a text console w3m browser called w3m-img

What catch my attention on w3m-img is the browser ability to display pictures in plain console tty or terminals.

Here is the description returned by apt-cache show w3m-img

debian:~# apt-cache show w3m-img|grep -i description -A 3
Description: inline image extension support utilities for w3m
w3m-img provides some utilities to support inline images for w3m
on terminal emulator in X Window System environments and Linux
framebuffer.


w3m-img doesn't rely on svgalib for displaying the pictures, but comes with its own written console image display & rendering library called w3mimgdisplay. - /usr/lib/w3m/w3mimgdisplay.

One w3m-img pre-requirement in order to be able to display pictures in plain text console ttys is to have Linux kernel framebuffer enabled..
Actually, framebuffer is enabled by default on latest stable Debian and derivatives as well as on most other Linux releases as of time of writting this post).
Also framebuffer is active for RPM based distros (Fedora, CentOS, SuSE) etc.

The Frambebuffer on or off is controlled via some directives added in grub or lilo configuration (depending on the installed boot loader).
Here is the time to say, some people can only boot their PCs with the framebuffer kernel support switched off at boot time. Unfortunately this unlucky ones, would not be able to use the picture rendering w3m-img cpabilities.

For people who can't run their Linux distro with a framebuffer kernel support enabled there is a custom hacked version of links - console text browser called links-graphic. links-graphic supports both console graphical text browsing using the framebuffer or alternatively svgalib as a console graphics render machine.

I used to be actively, using links-graphics quite often about 8 years ago and remembering it brings me good memories of the good old console "hacking" years :)

Anyways, w3m-img packaged version is currently available for both rpm and deb based Linux distributions. Here is how to install on both.

1.Install and use w3m-img on Debian, Ubuntu, Mint Linux-es

debian:~# apt-get --yes install w3m-img
....


This should install w3m-img, if there is already no previous install of w3m package on the system.
In case you have the w3m deb installed, you will have to first remove the existing w3m installed version before insatlling the w3m-img package, otherwise you will probably end up with an installation conflict (at least I got such a dependency conflict while apt-getting). Probably the conflict would never occur if aptitude install w3m-img is used instead ....

Using w3m-img is exactly the same as using the w3m text only browser version. Below is a screenshot example of w3m-img in action:

debian:~# w3m http://images.google.com






As you can see in the upper screenshots w3m-img displays pictures pretty nice, whether iven images.google.com search functionality works fine.
Generally a lot of pages looks cool with w3m-img.
Some elements placement comes odd but this is normal since w3m text browser doesn't have any support for javascript.

For those people who would like to have both javascript basic support and images in a plain text console browsing you, again you will have to compile links from source manually with svgalib support enabled.

2. Installing w3m-img to text-browse with images on Fedora, CentoS, RHEL, Redhat etc.

[root@centos ~]# yum -y install w3m-img
....


A very cool thing of w3m graphical console support is its support for most major image formats including animated GIF files :)

The way animated GIFs are viewed is very old school, here is a notice extracted from README.img

Notice
If you want to see GIF animation, please hit a suitable key, such
as 'h', 'l', etc., repeatedly, because a frame is rewritten
according to the re-drawing demand from w3m.
Some code in w3mimg/fb/fb.c was originally written by Mr. Yamasaki.
http://www.sainet.or.jp/~yamasaki/download/fb-sample.tar.gz

As one can read in order to see an animated GIF file with w3m you will have to keep pumping the h or l key or Enter key :D
Here is the also the complete list of Supported browser features mentioned in README.img

Support

* Display inline image (GIF,PNG,JPEG, etc.) on terminals
(xterm,rxvt, etc.) of X11 or Linux framebuffer device.
* Support inline image of tag.
Support of attributes "width", "height", and "align".
* Direct display of image file which header is "Content-type: image/*"
* Support of

Something else which I find worthy to mention is whether a webpage has a Adobe Flash .swf or .flv files embedded, they're simply ignored and the w3m keeps running stable (no strange flash crashes!).

While website with flash is opened in w3m, Adobe Flash's field on the screen shows either a blank rectangle or an empty square (depending on the site embedded flash banner dimensions and form).



Stability of w3m in opening flash website is something really nice. I say this because I still remember how terrible the situation with links with svgalib support was. Back in the day whether a "flash enabled" website was opened most of the time the browser was core dumping.

3. Install and use links2 on Debian and derivatives Linux to browse in console graphically with javascript support

As I mentioned earlier, there is a hacked version of links browser called links-graphics
This hacked version is available as a package within Debian, Ubuntu and presumably most if not all of the rest deb based Linux distros. On Fedora and the other RPM family Linuces links-graphics, should be downloaded separately as rpm and installed and is not available from default repositories.

On Debian distros links-graphics is available by installing links2.
debian:~# apt-get install --yes links2
....


Later to start links2 in graphics mode in lets say tty1 on a machine booted its kernel with framebuffer support, type:

debian:~# links2 -driver fb http://images.google.com


links2 looks, way better in console than w3m but this is quite normal, as links is way more user friednly text browser than its w3m competitor.

For those, using their console ttys without framebuffer enabled you can alternatively run links2 with its svgalib graphics support like so:

debian:~# links2 -driver svgalib -mode 320x200x16 http://images.google.com




Note that the svgalib driver is not working on my machine, as my Linux kernel framebuffer is enabled. Probably if I want to use links2 through the svgalib I will have to reboot and boot machine with framebuffer kernel support switched off...

links2 also supports X window graphics and is a great for Graphical environment browser substitute to CPU intensive Iceweasel / Firefox or Google Chrome. Links2 use as a default browser in X windows is a probably a perfect choice for scientiests and people who does not need support for Adobe Flash Playeror HTML5 standards.

To use links in XFCE or GNOME Desktop env, the quickest way is to prepare new Application Launcher to run command:

debian:~# links2 -g




Also I find it useful to use a quick alias to links -g in my ~/.bashrc in order to allow easier browsing from console by typing xlinks someurladdress.com

If you want to add the same shell alias as me issue:

debian:~# echo 'alias xlinks='links2 -g $1' >> ~/.bashrc


4. Install links with graphics console support on Fedora, CentOS and RHEL

[root@fedora ~]# cd /usr/local/src
[root@fedora src]# wget -q http://jakub.horky.net/rpm/links/links-2.1pre15-2/links-2.1pre15-2.i386.rpm
[root@fedora src]# rpm -ivh --nodeps links-2.1pre15-2/links-2.1pre15-2.i386.rpm
Preparing... ########################################### [100%]
Installing... ########################################### [100%]


If you get some errors with missing libraries after installing and launching links2, try to resolve them by manually linking them with ln or look for the library package rpm versions and install them via yum. Another alternative is to fetch the links2 source from Links2 official website links.twibright.com and build from source.

Since last time many years ago I used links2, I should say it evolved a lot. The version I tried did not crash, whether a flash websites are opened and generally it seemed to work quite stable.
To sum it up most people, will probably want to use Links2 for console graphical browsing as the speed and support for HTML and Javascript and web site formatting is way advanced than w3m-img

I haven't compared the speed of opening pages, but since w3m-img is html and graphics render is more simple than xlinks I suppose at some occasions w3m-img will be faster in site rendering. Still links2 performs really light fast and its web page opening time is swift, if compared to most if not all traditional desktop browsers used nowdays.

Using links2 instead of traditional desktop browser in some cases could improve website browsing time if properly used.

I haven't thoroughfully researched if there are other w3m-img, links2 alternatives programs for Linux / BSD. If you know amy other console browsers with image viewing support pls let me know.

Happy Browsing ;)

While reading some posts online related to MS-Windows TcpView - network traffic analyzing tool. I've came across very nice tool for tracking connection speed for Linux (Speedometer). If I have to compare it, speedometer is somehow similar to nethogs and iftop bandwidth network measuring utilities .
What differentiates speedometer from iftop / nethogs / iptraf is it is more suitable for visualizing a network file or data transfers.
The graphs speedometer draws are way easier to understand, than iftop. Even complete newbies can understand it without hassle. All this makes Speedometer, a top tool to visually) see the amount of traffic flowing through server network interface (eth0) ... (eth1) etc. on a network
What speedometer shows is similar to the Midnight Commander's file transfer status bar, except the statistics are not only for a certain file transfer but can show overall statistics over server passing network traffic amount (though according to its manual it can be used to also track individual file transfers).

The simplicity for basic use makes speedometer nice tool to track for network congestion issues. In my view it should be therefore a must have outfit for every server admin.



1. Installing speedometer on Debian / Ubuntu and Debian derivatives

For Debian and Ubuntu server administrators speedometer is already packaged as a deb so its installation is as simple as:

debian:~# apt-get --yes install speedometer
....


2. Installing speedometer from source for other Linux distributions CentOS, Fedora, SuSE etc.

Speedometer is written in python programming language, so in order to install and use on other OS platforms than Debian, its necessery to have installed (preferrable) an up2date python programming language interpreter (python ver. 2.6 or higher)..
Besides that it is necessery to have installed the urwid -( console user interface library for Python) available for download via excess.org/urwid/

a) Download & Install python urwid library

[root@centos ~]# cd /usr/local/src
[root@centos src]# wget -q http://excess.org/urwid/urwid-1.0.1.tar.gz
[root@centos src]# tar -zxvvf urwid-1.0.1.tar.gz
....
[root@centos src]# cd urwid-1.0.1
[root@centos urwid-1.0.1]# python setup.py install
running install
running build
running build_py
creating build
creating build/lib.linux-i686-2.4
creating build/lib.linux-i686-2.4/urwid
copying urwid/tests.py -> build/lib.linux-i686-2.4/urwid
copying urwid/command_map.py -> build/lib.linux-i686-2.4/urwid
copying urwid/graphics.py -> build/lib.linux-i686-2.4/urwid
copying urwid/vterm_test.py -> build/lib.linux-i686-2.4/urwid
copying urwid/curses_display.py -> build/lib.linux-i686-2.4/urwid
copying urwid/display_common.py -> build/lib.linux-i686-2.4/urwid
....


b) Download and install python-setuptools

python-setuptools is one other requirement of speedometer, happily on CentOS and Fedora the rpm package is already there and installable with you:

[root@centos ~]# yum -y install python-setuptools
....


c) Download and install Speedometer

[root@centos urwid-1.0.1]# cd /usr/local/src/
[root@centos src]# wget -q http://excess.org/speedometer/speedometer-2.8.tar.gz
[root@centos src]# tar -zxvvf speedometer-2.8.tar.gz
.....
[root@centos src]# cd speedometer-2.8
[root@centos speedometer-2.8]# python setup.py install
Traceback (most recent call last):
File "setup.py", line 26, in ?
import speedometer
File "/usr/local/src/speedometer-2.8/speedometer.py", line 112
n = n * granularity + (granularity if r else 0)
^


While running the CentOS 5.6 installation of speedometer-2.8 I hit the n = n * granularity + (granularity if r else 0) error.

After consultation with some people in #python (irc.freenode.net), I've figured out this error is caused due the outdated version of python interpreter installed by default on CentOS Linux 5.6. On CentOS 5.6 the python version is:

[root@centos ~]# python -V
Python 2.4.3


As I priorly said speedometer 2.8's minimum requirement for a python is to be at 2.6. Happily there is quick way to update python 2.4 to python 2.6 on CentOS 5.6, as there is an RPM repository maintained by Chris Lea which contains RPM binary of python 2.6. To update it run:

[root@centos speedometer-2.8]# rpm -Uvh http://yum.chrislea.com/centos/5/i386/chl-release-5-3.noarch.rpm [root@centos speedometer-2.8]# rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY-CHL [root@centos speedometer-2.8]# yum install python26

Now the newly installed python 2.6 is executable under the binary name python26, hence to install speedometer:

[root@centos speedometer-2.8]# python26 setup.py install
[root@centos speedometer-2.8]# chown root:root /usr/local/bin/speedometer
[root@centos speedometer-2.8]# chmod +x /usr/local/bin/speedometer


[root@centos speedometer-2.8]# python26 speedometer -i 1 -tx eth0


The -i will instruct speedometer to refresh the screen graphs every second.

3. Using speedometer to keep an eye on send / received traffic network congestion

To observe, the amount of only sent traffic via a network interface eth0 with speedometer use:

debian:~# speedometer -tx eth0


To only keep an eye on received traffic through eth0 use:

debian:~# speedometer -rx eth0


To watch over both TX and RX (Transmitted and Received) network traffic:

debian:~# speedometer -tx eth0 -rx eth0


If you want to watch in separate windows TX and RX traffic if you're running speedometer you can run in separate xterm windows speedometer -tx eth0 and speedometer -rx eth0, like in below screenshot:


4. Using speedometer to test network maximum possible speed between server (host A) and server (host B)

The speedometer manual suggests few examples one of which is:

How fast is this LAN?

host-a$ cat /dev/zero | nc -l -p 12345
host-b$ nc host-a 12345 > /dev/null
host-b$ speedometer -rx eth0


When I red this example in speedometer's manual, it wasn't completely clear to me what the author really meant, but a bit after when I thought over the example I understood it.

The idea behind this example is that a constaint stream of zeros taken from /dev/zero will be streamed over via a pipe (|) to nc which will bind a port number 12345, anyone connecting from another host machine, lets say a server with host host-b to port 12345 on machine host-a will start receiving the /dev/zero streamed content. Then to finally measure the streamed traffic between:
host-a and host-b machines a speedometer is started to visualize the received traffic on network interface eth0, thus measuring the amount of traffic flowing from host-a to host-b ...

I give a try to the above, using for two test nodes my home Desktop PC, Linux some arcane version of Ubuntu and my Debian Linux notebook, on the Ubuntu PC I issued

hipo@hip0-desktop:~$ cat /dev/zero | nc -l -p 12345

Note that I have previously had installed the netcat, as nc is not installed by default on Ubuntu and Debian.
The above command will not produce any output, but will display just a blank line this is exactly what it should do so don't panic, that there is no verbose output from it.

Then on my notebook I ran the second command example, given in the speedometer manul:

hipo@noah:~$ nc 192.168.0.2 12345 > /dev/null

Here the 192.168.0.2 is actually the local network IP address of my Desktop PC. The Desktop PC is connected via a normal 100Mbit switch to my routing machine and receives its internet by NAT. My second test machine (my laptop), gets its internet through a wi-fi connection received by a Wireless Router connected via a UTP cable to the same switch to which my Desktop PC is connected.

Finally to test / get my network maximum thoroughput I had to use:

hipo@noah:~$ speedometer -rx wlan0


I had to monitor my wlan0 interface, as this is my wireless card interface over which I have connectivity to my local network and via the wi-fi router I get Internet traffic routed to my Notebook.

Below is a snapshot captured showing approximately what is the max network thoroughput from:
Desktop PC -> to my Thinkpad R61 laptop




As you can see in the shot approximately the maximum network thoroughput is in between:
2.55MB/s min and 2.59MB/S max, the speed is quite low for a 100 MBit local network, but this is normal as most laptop wireless adapters hardly transfer traffic in more than 10 to 20 MBit per sec.

If the same nework thoroughput test is conducted between two machines both connected to a same 100 M/bit switch, the traffic should be at least a 8 MB/sec.

There is something, else to take in consideration that probably makes the provided example a bit inaccurate, the fact that the /dev/zero contained is stremed over is slowing down the 0 flows, as pipe use slows down the stream.

While reading speedometer manual, I've noticed another interesting application of the little nifty tool. The section in the man reads like so:

5. Using speedometer to visualize maximum writting speed to a local hard drive on Linux In the speedometer manual, I've noticed another interesting application of this nifty tool.

speedometer can be used to track and visualize the maximum writing speed a hard disk drive or hard drive partition can support on Linux OS:

The manual reads examply as follows:

How fast can I write data to my filesystem? (with at least 1GB free) dd bs=1000000 count=1000 if=/dev/zero of=bigfile &
speedometer bigfile


However, when I tried directly above example to test the maximum writting speed to an external USB hard drive, only dd get launched but the speedometer failed to initialize and show ascii graphs of the file creation speed (on the fly).

I've found a little "hack" that makes the man example work by adding a 3 secs sleep like so:

debian:/media/Expansion Drive# dd bs=1000000 count=1000 if=/dev/zero of=bigfile & sleep 3; speedometer bigfile


Here is a screenshot of the bigfile created by dd and tracked "in real time" by speedometer:



Actually the returned results from this external USB drive are, quite high, the possible reason for that is it is connected to my laptop over an USB protocol verion 3.

6. Using Speedometer to keep an eye on file download in progress

This speedometer tool is mostly useless especially on Linux Desktop. However in some occasions if files are transferred over ssh or in non interactive FTP / Samba file transfers between Linux servers it could be useful.

To visualize the download and writting speed of lets say FTP transferred .AVI movie file on the download host issue:

# speedometer Download-Folder/What-goes-around-comes-around.avi


7. Estimating approximate time for file transfer

There is another section in the manual pointing of an example, capable to rawly calculate the time remaining for a file transfer.

The example pointed in the manual reads like so:

How long it will take for my 38MB transfer to finish?
speedometer favorite_episode.rm $((38*1024*1024))


At first glimpse it is not very comprehensible, on the exact use of speedometer and, so I was puzzled. A bit of reasoning revealed what they meant the obscure calculation:

$((38*1024*1024))


Is a formula used in which 38 has to be substituted with the file size amount of the transferred file.
I give it a try - (just for the sake to see how it works) with a file with a size of 2500MB, in below two screenshot pictures I show my preparation to copy the file and the actual copying / "real time" transfer tracking with speedometer's status percentage completion bar.





That's all folks, happy hacking :)