Asrock ALiveNF6G-VSTA sound issue with Ubuntu Precise

Ubuntu precise is sometime unsettling at best. Audio won’t work with my old ALiveNF6G-VSTA. It used to be the reverse on Linux: old hardware would work, new hardware not always. Ubuntu Precise changed that altogether: old hardware isn’t working, and new hardware isn’t working either.

ALiveNF6G-VSTA motherboard. Photo courtesy of Asrock

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Playing with bluetooth GPS for fun and profit

I am recently fiddling with an old Bluetooth receiver to use it as a time source for my Arduino chrondot clock. Please note it’s already been done[] and an interesting graph of Chronodot drift is provided. First of all I decided to get a good look at the NMEA stream coming out of the GPS … Leggi tutto

Cryptswap and Linux assigning different devices letters to disk

I had this weird issue recently: I had a simple Ubuntu setup with cryptesetup and swap, and the crypt swap device (say /dev/mapper/mycryptoswap1) keept disappearing.
Caution: fiddling with cryptsetup and disk devices is dangerous for data and OS. I personally made a full backup on a separate disk and then umplugged it to be sure it wouldn’t be involved in any mishap.

Turns out is a little worse that that: Linux is changing the drive devices assignations (eg /dev/sdb /dev/sdg) at every boot under my nose. I did not notice at first because I am using UUIDs, so everything looked fine. Unfortunately my raw partition did not have any UUID.  Probably there’s a way to assign an UUID to a general partition, but I didn’t address this issue.
Having the disk changing its letter any time was the reason why the crypttab device wasn’t created a boot.  I was lucky: would a partition with valuable data be present in the other disk, it would be overwritten with encrypted swap data.

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Linux Kernel 3.6 is here

I had to upgrade a Pangolin Precise to Linux 3.6 to issue a bug on Linux Vs my Logitech mouse. So far I can say: Nvidia_current 295.40 fails to build module in 3.6.0 amd64 (I suspect it would also on i386) Solution: install nvidia-current 304.51 from ubuntu xedgers. Works out of the Box. Vmplayer VMware … Leggi tutto

NX machine, custom ssh configuration and on disk encryption for the faint of heart

Recently I switched an ubuntu test server running Precise Pangolin  from x11vnc to No Machine Nx server. I suppose (but haven’t tried) that those indications may also work for FreeNX (whose repository is unreacheable, at the moment)
As usual, it turns out that having a non-standard Ssh configuration or Ubuntu on disk encryption your mileage will vary, as NX machine relies heavily on OpenSSH. Also Ubuntu Precise  brings some issues of this own.

I recently detailed the length I had to go to ensure reliable ssh communication with home-directory-encrypting .
However I like to understand what happens under the hood so I decided to go ahead with the set up instead of just rolling back x11vnc.
It’s a test server, so let’s get over this.
Of course, I managed to do everything with the server “near” me. Doing this on a remote server is not a good idea, even  having something or someone with an alternative way of access on site. Things can go awry also after a reboot, because of the encrypted home file-system. Checking what happens after a full reboot before declaring ‘OK’ is a good idea.
Versions involved: nxclient,nxnode,nxserver  3.5.0-xx  running on Pangolin Ubuntu 12.04 LTS 64 bit.
Premise: I suspect a good deal of problems can be avoided installing and configuring Nx machine with the home directory (e.g the home of the user that is going to connect) mounted. One has only to remember then to cover all bases and modify the relevant directives and copy the relevant files outside the encrypted home. I did it without the home directory mounted.
Read everything before doing anything!

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Ubuntu oneric ocelot 11.10: adding a favourite lancher when you can’t use Keep in launcher

Sometimes in the new Ubuntu Oneric Ocelot 11.1 launching a program and selecting ‘Keep in launcher’ is not enough. This may happen if your program requires special startup parameters, or simply because it requires a terminal to run in, ala’ Matlab. Creating a launcher on the desktop is not simply as right clicking to ‘create launcher’ as it was in older versions.
I wandered a while before finding my answer here (thanks to Bruno Pereira), as others where that useful to me.

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