We have 2 DSS7 Lite servers with identical Raid config (1 x R5 & 1 x R1).

Almost every month the R5 Raid on both units rebuilds - is this normal?
We normally only ever use HW Raid (LSI), so this is a bit confusing, but we think maybe it's expected, but I can't find another post asking the same thing, so we need to ask!

This is from the critical_errors file...

dss1
01:06:01 02-11-14 info Rebuild of RAID MD0 started on host dc-dss1.
01:06:01 07-12-14 info Rebuild of RAID MD0 started on host dc-dss1.
01:06:01 03-05-15 info Rebuild of RAID MD0 started on host sdc-dss1.
01:06:01 07-06-15 info Rebuild of RAID MD0 started on host sdc-dss1.
01:06:01 05-07-15 info Rebuild of RAID MD0 started on host sdc-dss1.

dss2
17:47:59 24-05-14 info Rebuild of RAID MD0 started on host dss2.
01:06:02 01-06-14 info Rebuild of RAID MD0 started on host dss2.
01:06:02 06-07-14 info Rebuild of RAID MD0 started on host dss2.
01:06:01 03-08-14 info Rebuild of RAID MD0 started on host dss2.
01:06:01 03-05-15 info Rebuild of RAID MD0 started on host sdc-dss2.
01:06:01 07-06-15 info Rebuild of RAID MD0 started on host sdc-dss2.
01:06:01 05-07-15 info Rebuild of RAID MD0 started on host sdc-dss2.
01:06:02 02-08-15 info Rebuild of RAID MD0 started on host sdc-dss2.
01:06:01 06-09-15 info Rebuild of RAID MD0 started on host sdc-dss2.
01:06:01 04-10-15 info Rebuild of RAID MD0 started on host sdc-dss2.
01:06:01 01-11-15 info Rebuild of RAID MD0 started on host sdc-dss2.
01:06:02 06-12-15 info Rebuild of RAID MD0 started on host sdc-dss2.

Thanks for any advice.