Disk Recovery Part III

[Matthew Gillen]

Don Levey wrote:
> Hmm... Mirror the /boot partition too?  
Why not?  It's critical to booting your system...
The only reason not to would be if your boot-loader couldn't grok raid
partitions (I know grub can).

> Can I RAID these devices while the system is running?  That is, boot off the
> first of the two drives, edit the /etc/fstab to take the new partition names
> (md2, md3, etc) into account, edit the /etc/raidtab file to add the new RAID
> partitions, and then run mkraid on the running drives/system to synch up?
> Is that all there is to it?  Somehow it seems too easy.
Um, you can't (safely anyway) take an existing filesystem and make it
RAID.  Doing mkraid will (potentially) corrupt your filesystem.

What you could do is configure a RAID-1 disk with no mirrors, create
your filesystem, copy files, etc.  Then reboot with root=/dev/md#, and
*then* you can hot-add a mirror (your other disk).

> At the very least, I can probably get an FAQ out of this, though looking at
> the BLU website I don't see an FAQ section.

http://tldp.org/HOWTO/Software-RAID-HOWTO.html

--Matt