Linux Kernel 3.6 is here

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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

Wi-fi for PowerPC powermac G5

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I recently bought a PowerPC Powermac G5. I was very fond of this computer back in 2007, when for various reasons I could not afford it. Simply too much stuff for me!
Now I had it for a ridiculous price and got it back to life. A lot of RAM (DDR2 still come cheap these days), a new OS, some up-to-date apps. Of course the G5 didn’t have any Wifi card available, so I had to turn to the used market. There’s the standard Apple Airport card, but getting it is expensive, and I don’t want to spend a lot on this marvellous piece of hardware. Moreover I want to limit the direct tweaking inside the case as much as I can.

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

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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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Volunia is alive and kicking

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Whom the gods wish to destroy, they first call promising.
(Cyril Connolly, Enemies of Promise)

The Italian social search engine Volunia by Massimo Marchiori raised eyebrows during this launch of February 2012: some considered it  stillborn. The usual ill-fated comparison (e.g “the Google killer”) fuelled the debate further.
08/06/2012 Update: it seems there are some problems…read at bottom

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Openssh and the perils of encrypted home

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Let’s say you have just prepared a new server and you make all your stuff. Nowadays Linux distro have an option to enable home encryption for users, a feature I feel interesting for a system administrator as reduces the always present danger of leaving something valuable lingering around for an attacker.
It presents also a lesser know issue. If you use ssh Pubkey authentication (and you probably should by now) only, you may find yourself being out of the server in a subtle way, as OpenSsh will start refusing key intermittently, or SSH public key login  will fail for first login. It may seem a permission issue, at first. It may be not.

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