[TriLUG] Setting Up RAID-5

[David Brain]

>
> 3. if a disk dies suddenly, the system is gonna crash regardless of raid
> because the kernel can no longer communicate with /dev/sdx, it just
> disappears.  go ahead, set up software raid with hot swap disks then yank
> one out while the system is running, see what happens.  the data itself is
> probably ok (you'll have a degraded array upon reboot) but availability is
> shot.  plus your fstab may no longer be accurate once a disk is removed.
>

Not sure this is true in all circumstances, it may well be true for
non-hotswap capable hardware, but I had a drive die the other day in
an array where the only results were:

1. A lot of messages in log about SCSI timeouts.
2. A polite email from mdadm telling me that a drive had died.
3. Slightly lower performance as the hotspare was rebuilt.
4. Visit to colo to replace the bad drive and re-add it the the array
as the new hotspare.