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View memory brand, manufacturer & serial number in Linux

salubrium — Wed, 28 Jul 2010 04:59:25 +0000

Very simply.

sudo dmidecode –type 17

This gives the following output:

# dmidecode 2.9
SMBIOS 2.4 present.

Handle 0×1100, DMI type 17, 27 bytes
Memory Device
Array Handle: 0×1000
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 2048 MB
Form Factor: DIMM
Set: None
Locator: DIMM_A
Bank Locator: Not Specified
Type: DDR
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: AD00000000000000
Serial Number: 00001016
Asset Tag: 000818
Part Number: HYMP125S64CP8-Y5

Handle 0×1101, DMI type 17, 27 bytes
Memory Device
Array Handle: 0×1000
Error Information Handle: Not Provided
Total Width: 64 bits
Data Width: 64 bits
Size: 1024 MB
Form Factor: DIMM
Set: None
Locator: DIMM_B
Bank Locator: Not Specified
Type: DDR
Type Detail: Synchronous
Speed: 667 MHz (1.5 ns)
Manufacturer: AD00000000000000
Serial Number: 00003160
Asset Tag: 410801
Part Number: HYMP112S64CP6-Y5

Yakuake for Gnome

salubrium — Mon, 03 Aug 2009 00:53:29 +0000

I have previously written about Tilda, a gnome replacement for Yakuake. I had some issues with Tilda so I came to have a nice relationship with Yakauke. It’s important to note though, that there is another reasonable alternative to both Tilda and Yakuake and it’s called Guake.

Guake has some of the basic features of Yakuake but is still lacking in a few things. The main ones for me are:

Yakauke allows you to choose terminal width / Guake takes up fullscreen width. The advantage of this for me is that I can sit Yakuake on the right side of the page and read a web page as a reference if I am programming in vim or copying instructions for something.
Yakuake allows you to Alt+Shift+Left/Right to increase / decrease terminal width size on the fly. So if you can’t quite read the text you are referencing, it’s easy to shrink the terminal slightly so you can.

Still, if you are looking for a nice Gnome-based Quake style terminal window, Guake is a good alternative to both Tilda and Yakuake.

Bash command to determine multiple logins sorted by user with the most logins

salubrium — Thu, 29 May 2008 01:41:09 +0000

Here ’tis

w | awk ‘{a[$1]++}END{for(i in a){print a[i] ” ” i}}’ | sort -rn | head

stumbled on this issue with a HP-UX server we run where the maxusers kernel paramater is set to 600 (512 by default). To change this setting, requires a reboot of the server (something not easily achievable at midday with 600 users logged in). You can change kernel parameters via SAM in HP-UX

This is a slight modification of the 1 liner that sorts your bash history by commands used:

history | awk ‘{a[$2]++}END{for(i in a){print a[i] ” ” i}}’ | sort -rn | head

Here’s some examples of my own from 2 machines:

235 ll
163 cd
149 grep
37 vi
32 for
31 du
26 rm
23 tail
21 htop
20 /etc/init.d/httpd

Here’s my home machine (I use pkill when I login to the same user desktop remotely via NX to kill evolution in the console session) :

109 ll
42 sudo
35 locate
35 cd
24 pkill
17 more
15 vi
15 unison
15 ssh
14 echo

Technorati Tags: bash, hp-ux, linux, one-liner, awk, maxusers

How to schedule Linux to mute speaker volume overnight

salubrium — Mon, 28 Apr 2008 06:35:46 +0000

Here’s a simple method of automatically muting your volume overnight and resetting it in the morning. This is especially good for those who use softphones, skype or an IM client that have sound alerts output to speakers.

We are going to use three command line tools for this: aumix, which and cron. We are also only going to set things up so the commands are run under the user account, rather than as root as cron used incorrectly can open up some security issues.

so, to get started try and run:

:~$ aumix

and if it’s not there, try

:~$ sudo apt-get install aumix

for Debian / Ubuntu or

:~$ yum install aumix

for Redhat / Centos / Fedora

Now that we have aumix installed, we want to find out the path to the executable as Cron doesn’t always use our environmental variables to find executables on our path. So type:

:~$ which aumix
/usr/bin/aumix

We can see it’s in /usr/bin/aumix

So, kick-off your music player and try playing some music or other audio then run the following commands:

:~$ aumix -v 0

then

:~$ aumix -v 100

The first command should have dropped your volume down to 0% and the second command should have taken it back to 100%. Now that we have that working, let’s add it to cron. For myself, I don’t want to be disturbed between 11pm and 7am, so following cron’s options, we have

minute-hour-day-month-weekday-command – and we use 24 hour format. An asterisk means run at every instance of that time period, so:
* * * * * would mean every minute of every day, every month and
0 0 * * * would mean at midnight every day.

For myself, I want the 23rd hour of every day, every month for the volume to be set down and I want the 7th hour of every day for the volume to be returned to 90%. So we add this to our crontab:

0 23 * * * /usr/bin/aumix -v 0
00 07 * * * /usr/bin/aumix -v 90

To do so as a user, we use:

:~$ crontab -e

Now if your default editor is vim / vi and you have never used it before, you will need to learn a little vi before we get started. When the editor opens, type to enter insert mode allowing you to copy and paste the above code and modify for your needs, when you are finished editing, press esc then VV to save the file and exit.

If the above vi / vim is too difficult, then you can make nano your default editor (if it’s not already)

:~$ EDITOR=/usr/bin/nano

and then run

:~$ crontab -e

Nano is a simplistic editor with the basic instructions displayed at the bottom of the screen.

So, there you have the very basics of Cron administration – ie: the Task Scheduler of Linux and how to adjust your volume via the command line.

If you are looking for a GUI tool for Cron Administration, look no further than gnome-schedule:

:~$ sudo apt-get install gnome-schedule

here’s our beloved screenshot:

for raising and lowering the volume.

Technorati Tags: volume, linux, crontab, automation