Rebuilding a raid 1+0 (10) system

Question

We have a set of 8 disks that are raided together with RAID 10. Our software that rebuilds RAIDS do not allow a RAID 10 but does have a RAID 1 or a RAID 0. In theory, we wanted to drop the mirrored disks (four of them) and simply use the RAID 0.

My question is, are the mirrored disks forensickly equal? Will they have the same hash value? Right now we have 8 disks with 8 unique hashes. I would have thought that 4 of them would have a partner in exact matching hash.

Answer 1

The answers to this question would depend on the RAID software (and/or controller if you are using one).

I would expect (under Linux, using software RAID as the example I'm familiar with) that the disks would not be bit copies of each other because they need different signatures to identify how they fit into the array and identify them uniquely.

Depending on how the RAID was built I would expect the contents of the partitions to be bit-for-bit identical (although there may be some exceptions here - for example if your controller considers 2 disks new and identical, and does not do a full rebuild initially)

You also appear to expound a belief that RAID systems are all the same - they are not - they abstract the disk away from the computer, and may use different ways of doing this (and thats why I like software RAID, I have full control). With Hardware RAID its always advisable to have an identical spare controller in case the controller dies, and you get less access to the raw disk - and no guarantees you can even recover from it if the controller dies and you don't have an identical one).