Raid 1 + 0 - can fail too

Raid 10

You have a failed Raid 10 : Make Sure all drives are numbered and clearly marked

RAID 10 is implemented as a striped array whose segments are RAID 1 arrays

RAID 10 has the same fault tolerance as RAID level 1

RAID 10 has the same overhead for fault-tolerance as mirroring alone

High I/O rates are achieved by striping RAID 1 segments

Under certain circumstances, RAID 10 array can sustain multiple
simultaneous drive failures

Excellent solution for sites that would have otherwise gone with RAID 1
but need some additional performance boost


But did you know:

All drives must move in parallel to proper track lowering sustained
performance

Very limited scalability at a very high inherent cos




*Questions for the reader:


How many drives have failed? are they logical, electrical or physical
failures. Are the drives a matched set. Do you know if the failure of
the two drives was at the same time or has one drive failed and the
second went out at a later date?

Keep the order of the drives - number them before removing any drives.

Has the Raid been reinitialised? - if not DO NOT allow a reinitialisation

Are you able to supply the Raid controller?

Capacity of the drives (how many GB for each drive)
What type of drives (IDE ,SCSI, SATA)

Block Size used? (offset of starting block)
Details - additional RAID information