[KLUG Members] Question on RAID

[Adam Williams]

> You could.  I think most bootloaders will happily use a mirrored 
> partition.  If not, since /boot doesn't change very often, you have 
> another option.  Create a backup /boot on another drive, and put a 2nd 

I recommend the dual /boot solution.  It is the most fool proof.

> entry in GRUB or LILO that will boot from it.  Have a cron job that runs 
> once a week or so that synchronizes them.  Also, considering that your 
> bootloader is going to be installed on one of the drives that you're 
> worried about failing, a boot disk is highly recommended.

Yep, what he said.

> If you're going to use software RAID, though, you're going to want to 
> brush up on how you fail and replace a drive in the mirror:  
> "raidsetfaulty /dev/md0 /dev/hda1"  ... shutdown and swap ... 
> "raidhotadd /dev/md0 /dev/hda1".   For reasons I don't yet understand, 
> most of your RAID management commands are softlinks to /sbin/raidstart.  

That is done so that if these utilites are linked statically you only
need ONE file rather than multiple huge files.   Statically linked files
are frequency used in recovery scenarios.

> Did I mention the documentation for this is basically nonexistent?

ftp://ftp.kalamazoolinux.org/pub/pdf/DiskMan1.pdf

> As a side note, this same trick (except for the bootdisk part) works on 
> Windows servers too if you've got somebody who's too cheap to buy a real 
> RAID card!

Windows doesn't do software raid?