Ubuntu, RAID5, and You!

Phantasos

So here's the situation. I'm trying to set up a torrent box to sit on my network's DMZ and just run. I could have built a Windows one easily enough but I thought I'd play with the linuxes a bit and maybe learn something. I took 3 hard drives, broke each into 4 partitions (boot, swap, /, var), and then shuffled these 12 partitions into 4 RAID5 arrays. Easy enough. When I try to install Ubuntu, however, it gets halfway through the GRUB loader and just hangs. For hours. At which point I start looking for problems.

All the HDs have been scanned by the BIOS check disk and came up clean. I ran the check CD feature in Ubuntu and it got an error though I neglected to write it down (I tried 2 different burned discs, both verified after the burn but both came up with this error, however so I'm inclined to think that the CD is okay). Right now I'm DBANing the drives to start with a clean slate and scouring the internets to see if I can find any advice but haven't found anything that seems helpful.

Any help here would be greatly appreciated.

Apreche

First of all, what kind of RAID are you doing there? Hardware RAID, software RAID? Why did you put boot, swap, /, and var partitions on every drive? That's not how you make a RAID. The way you describe what you did leads me to believe you do not understand how file systems, partitions and RAID work in Linux.

As for the other problem, if you get a CD check error with multiple CDs in the same computer, try those CDs in another computer. If you don't get the error with another computer and the same CD, then either the CD-ROM or the drive controller of the first computer is busted.

Ubuntu Edgy RAID 5 Howto

Lastly, I suggest to people that you do not install your operating system on a RAID. Have one extra non-RAIDed drive to install your operating system onto. Treat your RAID as one giant hard drive with one giant file system on it. Mount it to /home/username or /home/username/media or something like that. I think you can see why this is a good idea.

Phantasos

I used the software RAID that's built into the alternate installer. Perhaps I wasn't as clear as I should have been with regards to how I partitioned. Here's the layout of what I built...

Drives 1-3
Partition 1 - 25 MB
Partition 2 - .5 GB
Partition 3 - 5 GB
Partition 4 - 74.5 GB

RAID5 Devices
MD1 - 50 MB /boot
MD2 - 1 GB /swap
MD3 - 10 GB /
MD4 - 149 GB /var

This way I was able to use my three 80 gig drives as 4 RAID5 partitions instead of one standard drive for the OS and either lose the redundancy with RAID 1 or lose the performance with RAID 2.

You're right that I'm not especially fluent with the nuances of partitioning Linux. A google search and some reading on my own led me to follow this HowToForge article which I relied upon heavily.

Once the DBAN finishes I'm going to try a single drive installation with the regular version of Ubuntu. If I get another CD error with that new image then it almost has to be the drive itself, in which case I'm pretty sure I've got a spare I'm not using around here somewhere. Thanks for the help.