Currently running 6.12.15 with a single parity drive configuration with two data drives.

 

The current parity drive is showing increasing reported uncorrect SMART errors, initially one, then another a few months later, then 5 at once recently. In between the errors I have done the usual mechanical suggestions, checking and reseating power and data connections, replacing sata cables, etc. While the drive still passes extended SMART without any bad/reallocated sectors I figure it is probably safer to replace it now as I have a replacement drive on hand. 

 

I have a few questions about what would be best practice here that I would appreciate any input on as this is my first go at having to replace a potentially failing drive, let alone the parity:

 

• It's been over 60 days since i last did a parity check, during which time the parity drive has experienced reported uncorrect errors. Prior to starting the parity drive replacement process, would it be advised to run a parity check? Neither of the data drives currently shows any SMART errors and given the errors reported with the parity drive I wonder if this is advisable.
• From what I gather, there are two ways I can add the new parity drive. Option 1 - add as second parity drive and start the array to to trigger the parity sync. Option 2 - replace old parity drive with new parity drive in the array setup (keeping it as unassigned in the even it is needed to rebuild) and start array in in maintenance mode to trigger the parity sync. I don't need access to the data drives during the sync process. Would offline be the safer of the two? Since the existing parity drive is suspect and may have issues, I wonder if having t in the array during the sync process would potential cause issues during the sync process or interrupt it if it starts throwing reported uncorrect errors again.

 

Thanks in advance for any suggestions.

3 minutes ago, DrewC said:

let alone the parity

Parity is the least important drive since it contains none of your data, and parity by itself can't rebuild anything. All the other disks must also be read to rebuild a missing disk, and the other disks do contain your data.

 

Not clear it needs replacing, but I would just replace parity and let it rebuild in normal mode.

2 minutes ago, trurl said:

Parity is the least important drive since it contains none of your data, and parity by itself can't rebuild anything. All the other disks must also be read to rebuild a missing disk, and the other disks do contain your data.

 

Not clear it needs replacing, but I would just replace parity and let it rebuild in normal mode.

 

Thanks for the quick response trurl.  Just to confirm, your suggestion would be to just remove the existing parity drive from the array config, add the replacement drive as the new parity drive in the array config, then start the array and trigger the parity sync?

To simplify and clarify

 

Shutdown - Replace parity disk - Reboot

Assign new parity disk - Start array to begin rebuild