I have upgraded my array from 4.7 to 5.0 in order to add a 3 TB parity drive (in prep for adding new 3 TB drives).  I precleared the drive and replaced the old 2 TB drive with the new, precleared 3 TB drive and restarted the array.  It is now doing a parity-sync.  I realize that I should have attached to old parity drive to a free port so that I could preclear it. 

 

My question: is it all right to cancel the parity-sync,  powerdown and insert the old 2 TB drive, reboot and restart the parity syn?.  Then I could preclear the old drive in parallel with the parity sync.

 

I have done some searching but I really cant find a definitive answer on what happens when you cancel the parity sync.  The web GUI says: "WARNING: cancelling parity will leave the array unprotected!"

 

Thanks.

I would not do that for one reason:  You don't want to destroy the old parity information until you have a good sync on the new parity drive.    It's unlikely that this will be a problem ... but why take a chance?

 

In fact, I would not only wait until the parity sync completes;  but I would then run a parity check to confirm that all went well  [a parity sync is NOT verified while it's done -- you need a parity check afterwards to confirm it's okay].

 

THEN I'd do the pre-clear on the old parity drive.    Note, by the way, that since the old parity drive has been well-tested in use, you can do the pre-clear in 1/4th the normal time by using the -n option to skip the pre- and post- reads.

 

I would not do that for one reason:  You don't want to destroy the old parity information until you have a good sync on the new parity drive.    It's unlikely that this will be a problem ... but why take a chance?

 

In fact, I would not only wait until the parity sync completes;  but I would then run a parity check to confirm that all went well  [a parity sync is NOT verified while it's done -- you need a parity check afterwards to confirm it's okay].

 

THEN I'd do the pre-clear on the old parity drive.    Note, by the way, that since the old parity drive has been well-tested in use, you can do the pre-clear in 1/4th the normal time by using the -n option to skip the pre- and post- reads.

 

Makes perfect sense.  That is what I will do.  Thanks again.