I'm new and this this my first topic. I bought an MD253 since 2 year ago but I never use it. I Bought this one to upload all pictures I have. I set the system in mirroring, in order to be a double copy of each picture on two HDs (Hitachi). I notice that when I switch off the NAS and then I restart it there the rebuilding of the second HD...is it normal?
For some reasons, sometimes there are little differences between the two disks in the array. When you turn on the nas, it checks the consistency of the array and founds that a resynch has to be done. You can easily check it in the log.
So the NAS starts rsynch.
Depending on how many GB you have inside the nas, this is a process that takes several hours. It might take half a day.
If you turn it off while it's still rsynching, the nas will launch rsynch every time you turn it on.
Try letting NAS turned on for a whole day. It the disks inside become too hot, put a fan in front of the nas and open its case.
Every now and then check between log lines if rsynch has ended.
Only at this point you can turn the nas off.
Next time you will turn it on, it won't do the rebuild again.
Hope it helps.