I am moving a parity drive into the array. I put a new 3TB drive as the Parity, and want to replace a 1TB drive in the array with the old parity drive-a 2TB drive. None of the drives are failing, but I am out of SATA ports, so I am shuffling. (I ran a stock flash to pre-clear the new parity drive)

 

From what I have gleaned from the FAQ's and the forum, I don't need to fully pre-clear the drive. I thought I remembered something about running preclear with some command or other to prep the drive for the array. But, I also saw in the manual instructions for replacing a drive when the parity drive is bigger (replace the parity drive, then just put the parity in the array).

 

Can I just plug the old parity drive in and assign the old drive's slot to it and let the system rebuild?

Stop the array;  unassign the drive you want to replace;  then Start the array so it shows the drive as "Missing".

 

Now shut down and plug in the drive you want to replace it with.    Then boot; assign the drive to the slot where the old drive was; and then Start the array ==> UnRAID will then rebuild the drive's contents on your new (larger) drive.

 

I would have totally skipped the unassigning step. Thanks Gary!

 

My big question is more about the ex-parity drive, do I need to do anything with it before I swap it out?

I would have totally skipped the unassigning step. Thanks Gary!

 

My big question is more about the ex-parity drive, do I need to do anything with it before I swap it out?

 

No -- if you're going to rebuild it, than pre-clearing it doesn't save any time.    And since it's been in service for (I presume) a good while, it's already thoroughly "tested" ... so I don't see any reason to run another pre-clear on it.  You may want to look at the SMART parameters to confirm it passes SMART and doesn't have any worrisome parameters.