No subject

[Liam Proven]

On 06/01/2008, Chris Lemire <good_bye300 at yahoo.com> wrote:
> Raid 0 has the risk of data corruption that usually happens after a certain
> amount of time. Is using LVM2 for striping safer than raid 0?

Is this meant to be a comment to another post?

RAID0 means striping. That is in itself risky; RAID0 is a performance
measure for non-critical data. If the data is in any way important,
don't put it on a stripe, put it on a mirror: RAID1. I don't know what
you mean about "corruption after a certain amount of time"; in a
stripe, if 1 disk fails, you lose everything. It's not gradual and
it's not corruption; you simply increase the chance of failure by
dividing the MTBF by the number of disks. The MTBF with 2 disks is 50%
that of a single drive; that with 3 disks is 33.333r%, and so on.

It doesn't matter /how/ you stripe. The risk is the same.

If you want reliability, don't use RAID0. Use RAID1, mirroring, or
RAID5 or RAID6 if you have enough disks.

RAID levels 5 and 6 are slower because of the need to compute parity;
if you have 4 disks or a multiple thereof, use RAID 10 or 0+1, a
stripe set of mirror pairs or a mirrored pair of stripe sets.

If, with modern hundreds-of-gig drives, this gives you awkwardly large
units of storage, on the order of Terabytes, then run LVM on top of
your RAID.

-- 
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