Yes, and it's a pain, but if you have to deal with it I think the
wealth of options in md leaves you better able to handle it than
with hardware RAID. Here's something that happened to me:
http://strugglers.net/wiki/becks.strugglers.net
Ouch.
How does hardware raid deal with this? Does it?
Thanks,
A.
Andy Smith wrote:
On Sun, Feb 12, 2006 at 11:31:07AM -0800, it wrote:
The hardware raid does the mirroring on the block level, so it's
actually /dev/sda mirroring /dev/sdb - the whole drive, and not
partitions. There is a way to set this up on software raid. It takes
more configuration tweaking, but the mirroring then includes the
partition table as well. This way, if a drive fails, one can replace it
without pre-partitioning it.
That can be less flexible though. If I have say 4 drives then I
quite often want small /boot, / and swap under RAID-1 then the rest
as a single large partition in RAID-5, -6 or -10 as an LVM PV.
This also raises another point, which is relevant for both cases - same
exact models of hard disks have different number of cylinders, so if a
RAID partition is created on a larger drive it cannot be mirrored to a
smaller drive.
Same exact models don't usually have different block counts, but
certainly if you replace a dead drive with a different one of the
same advertised capacity you can end up getting one slightly
smaller.
Does anyone have any experience with this?
Yes, and it's a pain, but if you have to deal with it I think the
wealth of options in md leaves you better able to handle it than
with hardware RAID. Here's something that happened to me:
http://strugglers.net/wiki/becks.strugglers.net
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