Hardware

Atom 330 Video encoding

As you probably know by now I purchased the TranquilPC BBS2, ATOM 330 based box with raid.  I am running ubuntu server 64bit.

I have quite a lot of dvd images on it, and access them from my media center, but to save space I wanted to encode them as mp4 so I installed the  64bit handbrakeCLI on it, not being bothered if it was going to take a few hours to re-encode the dvds.

Now my acer Core duo 2.0gb laptop encodes at about 80 frames/second which I have always been happy with, so I was very surprised to see that the Atom330 1.6Ghz, with it’s 2 hyperthreaded calls managed a very respectable 65 frames/sec!

Back to the Future III took 42 minutes to encode as mp4 720×576.

General

Some of the most beautiful fonts on the web for Free

I recently came across http://www.fontspace.com which IMHO is the best free font resource on the web, the planet, and possibly the whole universe… For years I have used GRSites.com as the place to get fonts, which does indeed have thousands. However GRsites only has navigation by font name and it has become slow and in comparison to fontspace in clumbersome.  Fontspace, not only tags each font, but you can choose the preview text and size tthat you want to the view fonts in.  Have a good look round and you’ll never want for a font again.

General

NNSA & IBM build super super computer

I read today in Linux Format that IBM are working with the US National Nuclear Security Administration to build a super computer with the following specs: 20 petaflops of processing power, 1.6 petabytes of memory and 1.6 million processing cores ! It will be 10 times more powerful than the current fastest super computer. I am all for super computers but working with the organisation responsible for the USAs nuclear defence is just silly in my book. Have they not seen the films? I am surprised the project is not called Skynet.

General

Thecus N2100 replacement fan

The fan on my Thecus N2100 is getting a bit noisy. I am sure it is starting to fail. Trying to get hold of a new one is a nightmare. However, I have eventually found a potential replacement at Maplin.co.uk. I will let you know if it all works.

UPDATE: The above fan from maplin.co.uk works a treat. Fits perfectly (had to tie up the cable to keep it neat and tidy as it is a bit long). It’s brushless, very quiet, has the right connector and works with the two speed settings in the thecus admin interface, even reporting the RPMs. It was a £8 gamble and it paid off 🙂

Hardware, Linux, Ubuntu

Ubuntu Server – Creating an expandable Raid5 Array starting with 2 disks

Again, I’m using VirtualBox to test this, I have a single OS drive with Ubuntu Server (intrepid) installed. I’ve added two 2gb virtual disk to it, which will be the starting point of the Raid5.  Most places on the net say you need at least 3 disks to run raid 5, but let’s see what happens.

Lets create the raid:

mdadm --create /dev/md0 --level=5 --raid-devices=2 /dev/sdb /dev/sdc

The raid gets created! and we can monitor it with

cat /proc/mdstat

When it has finished intitialising, create a file system on the raid array (ext3):

mke2fs -j /dev/md0

create a mount point (/raid) and mount it

mkdir /raid
mount /dev/md0 /raid

df then reports it as having 2Gb free.  Both my VM drives sdb and sdc are 2Gb, so the assumption is it is simply mirroring the data in 2 drive mode.  This is exactly what we want, as when I get a new drive later on, I want to add it to the raid and see an increase in disk space.  So lets test that, shutdown my machine and add a new drive.

Add the drive to the array

mdadm --manage --add /dev/md0 /dev/sdd

now when I run cat /proc/mdstat it says there are 3 drives in the arras but sdd is marked (S)

Lets now grow the array

mdadm --grow --raid-disk=3 /dev/md0

Watch the progress with cat /proc/mdstat and when complete we can mount it. (adding the 2Gb took about 5 mniutes! eeek! to grow the array).

After completion /proc/mdstat now reports 4gb available, but the file system on the raid still thinks it’s 2gb.

So let’s resize it:

e2fsck -f /dev/md0
resize2fs /dev/md0

Re mount /dev/md0 and df now reports 4Gb.

Success.

Hardware, Linux

Ubuntu Server-Reinstallation and re-configuring existing Raid1

Following on from my article on Setting up and Managing Raid1 on Ubuntu Server, I have been testing the raid using a VirtualBox VM.

Today, I took the VM, consisting of an OS drive (with Ubuntu Server installed) and 2 drives set up in raid 1 configuration and created a new OS drive, replacing the existing OS. The intention is to test inserting a new OS drive, re-installing the OS and getting the raid working again without loosing any data.

Useful Reference the mdadm man page

I installed the OS and installed mdadm as per the instructions in my previous post.

All commands are issued as root / sudo

So let’s see if can obtain any information about the raid, we’ll see what it knows about sdb1 which was part of the raid 1 with sdc1:

mdadm –examine /dev/sdb1

It successfully detects that the drive has a superblock and knows that it was part of a raid with /dev/sdc1. See the last two lines of the output.

So lets try to re-assemble the raid.

mdadm –assemble /dev/md0 /dev/sdb1 /dev/sdc1

It responds saying /dev/md0 has been started.

So now we only need to create a mount point

mkdir /raid

and mount it

mount /dev/md0 /raid

We have successfully mounted the raid so let’s now put an entry in fstab so it mounts at startup.

nano /etc/fstab

add

/dev/md0           /raid          auto     defaults        0      0

reboot and all should be working.