I am new to unraid and have just set up my array. First scheduled parity check returned 3285 errors. I thought this might be due to lots of power cycling when migrating data to the array to ran it again the following day. Again exactly 3285 errors. Both of these should have been correcting checks so suspicious the same value is given?

 

attach diagnostics to your NEXT post in this thread

10 minutes ago, paduffin said:

scheduled parity check

Were both of those checks scheduled? Most users schedule parity checks monthly, some even less frequently. Unraid parity is maintained realtime, so parity checks are not needed to maintain parity, they are just a check to verify that parity is correct.

 

Scheduled parity checks should be NON-correcting. You don't want an automatic parity check to (incorrectly) update parity if there is some other problem going on.

 

14 minutes ago, paduffin said:

lots of power cycling

Why? Shouldn't normally be necessary.

 

How are you shutting down? You must shutdown from the webUI. If you do a hard shutdown, that will parity check for unclean shutdown on next boot, since some parity errors can result.

 

It has been three weeks since I encountered the issue. I have now powered down and double checked the sata connections on all drives and I am running a new parity check. If this also returns errors I will attach the diagnostics. 

To answer your questions:

• The first check was scheduled but the second I ran manually the next day after seeing the errors. I have it scheduled once every three months.
• I will change the scheduled check to be non correcting. Thanks for the advice.
• The "lots of power cycling" was because I was migrating data from a hardware RAID5 with an external raid controller. I won't go into the details but it was a nightmare. I'm glad its over and the data is now on the unraid array. 
• I am shutting down using the webUI