Posts Tagged ‘sudo’

How to fix multiple instance music streams with sound card (Intel 82801I ICH9 Family) alsa sound problems on Ubuntu 11.04 GNU / Linux

Thursday, October 27th, 2011

Ubuntu Logo Sound / Pulseaudio multiple sound channel issues

The Ubuntu Linux installed previously on Acer ASPIRE 5736Z on my sisters notebook works quite fine. However today she complained about an issue with her sound. The explanation of the problem she faced is:

When she plays a movie file and pauses it and then switches to a music player, suddenly the notebook sound disappears completely until she restarts all the running programs using the sound server. The Acer Aspire is used with a GNOME Desktop, hence my bet was the issues are most probably caused by some kind of mess happening inside Pulseaudio or the way Alsa loaded kernel drivers handles the multiple sound channel streams.

I’m using GNU / Linux for more than 11 years now and I have faced the same sound issues so many times, so when I heard about the problem I thought its pretty normal.
Anyways, what was really irritating in these situation is that when her laptop sound disappears a video or sound files which are to be played by Mozilla Firefox Browser or Chrome are also loosing the sound.
This causes big issues, especially taking in consideration the fact that she had no idea about computers and is a GUI Desktop user, who have no idea how to restart the pulseaudio server to fix the problem etc.

As a good brother, I took the time to check about the issues related to the specific model of Audio Module Hardware / Sound Card, first I checked the exact model of audio the Acer Aspire 5736Z is equipped with:

stanimiraaaa@Ubuntu-Aspire-5736Z:~$ lspci |grep -i audio
00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03)

I checked about any reported other users issues on the net and I found a user somewhere (lost the link), complaining he is experiencing the same sound oddities on his Acer ASPIRE

The fix he suggested is actually quite simple and comes to adding a simple line to /etc/modprobe.d/alsa-base.conf :

stanimiraaaa@Ubuntu-Aspire-5736Z:~$ sudo su -
[sudo] password for stanimiraaaa:
root@Ubuntu-Aspire-5736Z:~# echo 'options snd_hda_intel model=auto' >> /etc/modprobe.d/alsa-base.conf

Next I restartarted to make the new settings take effect. Its also possible to do it without restart, by unloading and loading the alsa module but I’m a lazy kind of person and the machine is notablyunimportant so why should I bother 😉

One important note here is that I removed also an .asoundrc file, that I created some long time ago and this file might have been creating also some sound issues, the content of ~/.asoundrc, before I delete it in her home user, was like so:

stanimiraaaa@Ubuntu-Aspire-5736Z:~$ cat ~/.asoundrc
pcm.!default {
type hw
card 1
device 0
}
ctl.!default {type hw
card 1
device 0
}
stanimiraaaa@Ubuntu-Aspire-5736Z:~$ rm -f .asoundrc

Doing this minor changes to the Ubuntu system erradicated the sound problems and now the sound with simultaneous sound channel streams works just perfect! Thx God 😉

Runing sudo command simultaneously on multiple servers with SSHSUDO

Tuesday, June 21st, 2011

ssh multiple server command execute
I just was recommended by a friend a nifty tool, which is absoutely nifty for system administrators.

The tool is called sshsudo and the project is hosted on http://code.google.com/p/sshsudo/.

Let’s say you’re responsible for 10 servers with the same operating system let’s say; CentOS 4 and you want to install tcpdump and vnstat on all of them without logging one by one to each of the nodes.

This task is really simple with using sshsudo.
A typical use of sshsudo is:


[root@centos root]# sshsudo -u root \
comp1,comp2,comp3,comp4,comp5,comp6,comp7,comp8,comp9,comp10 yum install tcpdump vnstat

Consequently a password prompt will appear on the screen;
Please enter your password:

If all the servers are configured to have the same administrator root password then just typing one the root password will be enough and the command will get issued on all the servers.

The program can also be used to run a custom admin script by automatically populating the script (upload the script), to all the servers and issuing it next on.

One typical use to run a custom bash shell script on ten servers would be:


[root@centos root]# sshsudo -r -u root \
comp1,comp2,comp3,comp4,comp5,comp6,comp7,comp8,comp9,comp10 /pathtoscript/script.sh

I’m glad I found this handy tool 😉

Fixing / Resolving Fullscreen Adobe Flash issues in Debian Linux

Monday, April 11th, 2011

Adobe Flash Player ugly Logo!

If you’re experiencing problems with maximising flash (let’s say youtube) videos on your Debian or Ubuntu or any other debian derivative.
You’re not the only one! I myself has often experienced the same annoying issue.

The flash fullscreen failures or slownesses are caused by flash player’s attempts to use directly your machine hardware, as Linux kernel is rather different than Windows and the guys from Macromedia are creating always a way more buggy port of flash for unix than it’s windows versions, it’s quite normal that the flash player is unable to properly address the computer hardware on Linux.

As i’m not programmer and I couldn’t exactly explain the cause for the fullscreen flash player mishaps, I’ll skip this and right give you the two command lines solution:

debian:~# mkdir /etc/adobe
debian:~# echo "OverrideGPUValidation = 1" >> /etc/adobe/mms.cfg

This should fix it for, you now just restart your Icedove (Firefox), Epiphany Opera or whatever browser you’re used to and launch some random video in youtube to test the solution, hopefully it should be okay 😉 But you never know with flash let’s just hope that very soon the open flash alternative gnash will be production ready and at last we the free software users will be freed from the evil “slavery” of adobe’s non-free flash player!
Though this tip is tested on Debian based Linux distributions it should most likely work same in all kind of other Linuxes.

The tip should also probably have effect in FreeBSD, though the location of the adobe directory and mms.cfg should probably be /usr/local/etc/adobe, I’ll be glad to hear from some FreeBSD user if including the OverrideGPUValidation = 1 flash option to mms.cfg like below:

# mkdir /usr/local/etc/adobe
# echo "OverrideGPUValidation = 1" >> /usr/local/etc/adobe/mms.cfg

would have an impact on any flash player fullscreen issues on FreeBSD and other BSD direvative OSes that run the linux-flash port.