I have two data drives that have been disabled because of errors. I am preclearing two 18tb replacement drives right now but they are both larger than the parity drives so they will have to replace those first. I've replaced drives several times before but this is a little more complicated so I don't want to screw anything up. What's the best procedure for this situation? Will the array still be protected if those two are disabled and I replace a parity drive? I'm probably just being overly paranoid about this.

Since no data drive can be larger than the smallest parity drive you will need to use the Parity Swap procedure.   I suspect that you will have to do it twice, once for each failed data drive (but I may be wrong about that and you can do two at the same time, something I have never tried myself).

 

a point to check - are you sure the disabled disk are really faulty?   Drives often get disabled due to external factors rather than the drives themselves failing.  If you post your system’s diagnostics zip file we might be able to give you some feedback on that.

You can do the parity swap procedure for both disks at the same time but like mentioned you should post the diags first.

One of them is probably fine but the other one is over 7 years old so faulty or not, that one's getting replaced. I was hoping to avoid having the array unavailable.

tower-diagnostics-20221010-1721.zip

Edited October 10, 20223 yr by bobbintb

Diags are after rebooting so we cannot see what happened but disk3 looks fine, disk7 should be replaced since there's a failing NOW attribute, parity swap requires that the array be offline during the parity copy part, it will be online for the rebuild.

Cool, thank you both. Things are moving along now.