[sclug] RAID 5

[Alex Butcher]

On Thu, 22 Sep 2005, Tim Sutton wrote:

> Could I flip the question around a bit and ask :
>
> - Which distro makes raid configuration easiest (debian based preferably)?

I gather Debian uses RH's Anaconda installer these days. In which case, I'd
expect Debian to now be as easy as RH has been for the last few years.

> - How can we set up the raid so that it will boot successfully if any
> of the disk fail - we tried to set up /boot on a CF device but were
> unable to get debian to boot from it even after getting a CF -> ide ->
> sata converter so that all devices on the machine appear to the bios
> as sata?

I'm surprised that's the case, if the SATA controller is properly supported,
and is configured correctly in the BIOS. I'd expect to be able to set that
up with RH/Fedora fairly easily. If you're still at the test stage, give
CentOS 4.1 or FC4 a whirl.

> - What exactly is the difference between the active and inactive
> partitions?

Active partitions are also known as 'bootable'. The standard Windows NT MBR
will jump to the active partition's boot sector. I can't remember what the
DOS/W9x MBR does, and LILO/GRUB ignore the active/bootable flag, IIRC.

> - how can we clone the /boot partition across all disks (Im thinking a
> cron job here, but can I clone the mbr to all disks and have the
> second in line disk boot if the normal boot drive fails)?

dd?  The partition tables will need to be identical.

> - can teh boot partition be in the raid? I seem to recall mandrake
> used to allow that with its partitioning tool, but Ive never met
> another distro that lets me do that...

Depending on the RAID level, that might be a bug in Mandrake's installer.

The only RAID level that is compatible with /boot's role is RAID1.

> Many thanks
> Regards
> Tim

Best Regards,
Alex.
-- 
Alex Butcher      Brainbench MVP for Internet Security: www.brainbench.com
Bristol, UK                      Need reliable and secure network systems?
PGP/GnuPG ID:0x271fd950                         <http://www.assursys.com/>