When the WD Mybook Live 3TB NAS was released, I went out and bought one and promptly put all my stuff on it. I have never kept anything *really* important on there as I didn’t have anything to back up all that data on to. Anyway, the NAS was destroyed in a thunderstorm one day but fortunately the hard disk still worked. Unfortunately the way WD formats these NAS hard disks is very strange indeed. Normal means of recovering data from them don’t work. Scouring google for tips on how to get your data back results in nothing useful.

I tried various hard disk enclosures.. these have no chance as they all pretty much only support up to 2TB disks. I tried various ext2/ext3 windows drivers.. no good. I tried linux machines with custom built kernels.. also no good.

There are basically three problems:

1. The hard disk is big, USB enclosures hate that
2. The hard disk uses a (new) GTP partitioning scheme, older versions of Linux will struggle.
3. The hard disk ext4 partition (the one with all your data on) is formatted using 64kb sectors. This is the biggest hurdle as your PC running linux will not be able to mount it!

To recover your data:

A rough understanding of Linux is useful. In short you’re going to need to get the hard disk out of the NAS enclosure, stick it into a PC running a recent(ish) version of Linux and mount the partition using fuseext2. The trick to being able to mount the 64k sector disk is to avoid directly mounting it using the most excellent fuseext2 package. You’ll also need somewhere to put the recovered files – maybe another WD NAS? Maybe not

Step by step:

1. I recommend getting an old PC (with sata ports inside) and an old hard disk for installing Xubuntu (no need for ‘heavy’ Ubuntu) on. Don’t plug in your WD hard disk yet, you don’t want to accidentally format it!
2. Once you’ve installed xubuntu or whatever you’re using, turn off the machine and plug in the WD hard disk. Boot it back up again.
3. Start a terminal and type:
   

   sudo apt-get install fuseext2 parted
   sudo parted -l

4. The parted -l command will show you hard disks and partitions labelled /dev/sd.. something. You will see both the hard disk you installed linux on and the WD hard disk. The WD one will have a label such as: Model: ATA WDC WD30EZRS-11J (scsi), have a look down the list of partitions for the big ext4 one, like this:
   

   4      4624MB  3001GB  2996GB  ext4         primary

   Make a note of the disk (/dev/sdb) displayed underneath the hard disk model, and the partition number (in my case number 4). The path to the partiton for me is /dev/sdb4 (it may be different for you).

5. Now you’re ready to mount the disk. To make life easier for you non-terminal types, I’ve provided instructions on mounting it in your home directory:
   

   sudo mkdir -p ~/WD
   sudo fuseext2 -o ro -o sync_read /dev/sdb4 ~/WD 

You may hit various hurdles along the way. I’m not entirely sure if older PCs can support really big hard disks. If you’re using an earlier mybook world or something I believe they used XFS and software raid partitions which this blog post isn’t really about.

Remember, always back up anything you care about!

Please let me know if you found this useful, and link to it so it helps others stuck in the same situation!!

More info: Mounting filesystems > 4Kb block sizes on Linux

For about a year I noticed that very infrequently my VPS would run out of memory.. at first I thought it was probably just a wordpress plugin, but after a while I discovered it was actually saslauthd. This is a known bug (not known very well though..) with saslauthd on Debian. Anyway, here’s the fix – I’m not totally sure of the implications, so if you run a busy mail server I’d recommend you look into it a bit more before doing it:

I changed this line:

Update the file: /etc/default/saslauthd

OPTIONS=”-c -m /var/run/saslauthd”

to:

OPTIONS=”-c -m /var/spool/postfix/var/run/saslauthd -r”

I think this basically disables threading and enables forking of the process (or something like that) which is what was responsible for the memory leak.

So if you’re running out memory on your server, maybe give this a try

[Thanks to Djamu: http://www.howtoforge.com/forums/archive/index.php/t-52750.html ]

I recently upgraded from a WDTV media player to a WDTV Live. The WDTV is just a simple set top box that allows you to play video on your tv, much like an xbox 360 and a whole bunch of other devices. The WDTV live allows you to play stuff over the network which opens up a whole host of cool stuff if you use the mediatomb DLNA server software available for linux (google tversity if you want something similar for windows..)

Anyway, I managed to get my wdtv live to play the live TWiT (http://live.twit.tv) video stream – meaning I now have a real internet tv station right up on my tv!

This is a bit rough and ready, but hopefully I’ll improve it over time. You’ll probably need to have a rough idea of what you’re doing.

Make sure transcoding is set to yes in the config:

<transcoding enabled=”yes”>

In mime type profile mappings in the config:

<transcode mimetype=”video/x-flv” using=”ffmpeg”/>

So anyway, you’ll want to add this profile to your config:

<profile name=”ffmpeg” enabled=”yes” type=”external”>

<mimetype>video/mpeg</mimetype>

<accept-url>yes</accept-url>

<first-resource>yes</first-resource>

<accept-ogg-theora>yes</accept-ogg-theora>

<agent command=”/usr/local/bin/ffmpeg-tr.sh” arguments=”%in %out” />

<!– <buffer size=”14400000″ chunk-size=”512000″ fill-size=”1024″/> –>

<buffer size=”5242880″ chunk-size=”102400″ fill-size=”1048576″/>

<hide-original-resource>yes</hide-original-resource>

</profile>

Type: External Link (URL)

URL: http://bglive-a.bitgravity.com/twit/live/high

Protocol: http-get

Class: object.item.videoItem

Mimetype: video/x-flv

A special thanks to aTc from #mediatomb on irc.freenode.net – without whom this wouldn’t exist.

Ok, so I decided to natively install Ubuntu 10.04 on my Studio 1555.. fairly impressed.. almost everything works out the box which is a bit annoying.

The only issue I’ve had is that the included proprietary ATI driver fails when you try to use suspend, however this is apparently easily circumvented by using the most recent driver from the ATI site (it was a bug with their driver.)

Using the open source driver results in poor power management, so I’d advise against doing that.

Trac is pretty easy to set up on Debian, here’s a mini guide of what I did to get it working nice and quick. You’ll probably want to configure users etc afterwards, but this should be enough to get going.

Install:

apt-get install trac libapache2-mod-wsgi


Initiate the trac environment:

trac-admin /var/www/srdev/trac/ initenv


Set permissions:

chown -R www-data /var/www/srdev/trac/


Install the wsgi script and web resources. The first argument before ‘deploy’ should match the install environment (the path above.) The second argument following ‘deploy’ can probably go anywhere, but I just shoved it in the trac dir.


trac-admin /var/www/srdev/trac/ deploy /var/www/srdev/trac/www/


Next, we need to tell apache how to call the wsgi script, we do this using an alias. You can use / if you just want it to be in the same dir as your virtualhost, but in my case I wanted trac to be in a sub directory of the site (www.mysite.com/trac.) Add this to your virtual host (/etc/apache2/sites-enabled/whatever.)

The directory directive specifies some permissions for the script.

WSGIScriptAlias /trac /var/www/srdev/trac/www/cgi-bin/trac.wsgi
<Directory /var/www/srdev/trac/www/cgi-bin/trac.wsgi>
WSGIApplicationGroup %{GLOBAL}
Order deny,allow
Allow from all
&lt/Directory>


Finally, enable the wsgi module, and then restart apache. Now it *should* work

a2enmod wsgi
/etc/init.d/apache2 restart


*Updated!

The xbox360 doesn’t like divx/xvid files that have ac3 sound tracks, so we can use mencoder to convert these files so they use 128kbit stereo mp3 soundtracks instead. This isn’t too hard to do, just use a command similar to:

mencoder input.avi -ovc copy -oac mp3lame -lameopts cbr:br=128 -channels 2 -o output.avi

Easy when you know how.

I recently purchased the Edimax EW-7728IN IEEE802.11n Draft 2.0 wireless card. Although I’ve not tested the performance yet, I have managed to get it to successfully connect to my Billion 7300N 802.11n wireless router at a rate of between 270 and 300Mb/sec.

Before I began I read on the Ubuntu forums that many people had problems trying to get the thing to work. I found it was fairly straight forward which is probably a result of the new(ish) drivers on the edimax website for Linux.

You can download the latest source from http://www.ralinktech.com/ralink/Home/Support/Linux.html – I didn’t see any restrictions or licenses on there for the source, so I’ve decided to compile and upload the modules as I need them. You can check back here to pick up the latest if you’re not confident compiling it yourself.

Please don’t try running the modules on kernels that they are not for. This will not work! You will need to compile it against headers for your currently running kernel if you don’t find it listed here.

Then you’ll want to extract the kernel module:

bunzip2 rt2860sta.ko.bz2

Now test that it works before you continue:

sudo insmod rt2860sta.ko

Now run iwconfig to see if the module loaded OK. If so, you should have the ra0 device listed.

If all is well, copy the module to the kernel module directory:

sudo cp rt2860sta.ko /lib/modules/2.6.24-19-generic/ubuntu/net/rt2860/rt2860sta.ko

Now we’d like to tell it to auto-load upon system startup. We can do this by adding the line: rt82860sta to the /etc/modules file. Easy!

Update!!

I’ve recently found a link to a dynamically building kernel module .deb file, which is great because it means you can just install this .deb on your system and it should work. With a bit of luck the Ubuntu team will include the driver in Intrepid, but I wouldn’t hold your breath:

http://www.array.org/ubuntu/dists/intrepid/eeepc/binary-i386/rt2860-dkms_1.7.1.1_all.deb