A couple of days ago I came across a bit funny web site – www.raid-failure.com on which one can get different types of predictions for a particular RAID configuration. All you need to do is just fill the form with the following parameters:
in case of a RAID0
- how many member disks are in the RAID array,
- how old are the disks,
- needed optimism level used for prediction (similar to you believe that all will be OK, or you assume that things are bad).
For a RAID 5
- how many member disks are there in the RAID,
- size of a member disk,
- URE values according to vendors.
- how many groups are in RAID,
- how many member disks are in one group.
This free online RAID array failure estimator displays different predictions for different array types. If you have a RAID 0, then you will obtain a probability the RAID doesn’t fail within one to five years. For a RAID5, this calculator gives a probability to complete the rebuild and not encounter a failure; in case of a RAID10/50/60, you find out a probability to survive multiple disk failures.