Hi folks,

I have a question regarding disk size and a possible failure scenario.

I have eight disk in the server - 7x 12TB and one 8TB.

The situation is tricky because the 12TB disk is no longer available.

Its the first time since 2010, that i cant replace a disk with the propper size...

And now the question:

What happens, if the 8TB disk fails and i replace it with a 14TB disk?

Because the biggst HDD is always the parity drive, what happens with the data?

So when i replace the 8TB disk with a new 14TB disk, it becomes the parity - so far so good.

But during the rebuild process, what exactly is unraid doing?

Will it reconstruct the date and the parity at the same time?

Is this possible or may i be wrong?

Maybe a specialist can answer this question because its a really bad situation, "if" the 8TB disk fail in the future...

Thanks for your help

Edited January 31Jan 31 by Zonediver

The situation you describe is what the parity swap procedure is for.

Parity swap procedure isn't just about replacing parity. Some seem to think that because of the name, parity swap procedure is what they need to replace a parity disk.

What parity swap does, is copy parity to the new larger disk, then rebuild the failed data disk onto the old parity disk.

Parity swap is one of those phrases that automatically gets converted to a link into the documentation, so you can just follow the link for more details.

If you are ever unsure how to proceed in this or any other situation, please ask for help on the forum. Many ask for help after they have already made things worse.

6 minutes ago, trurl said:

The situation you describe is what the parity swap procedure is for.

Parity swap procedure isn't just about replacing parity. Some seem to think that because of the name, parity swap procedure is what they need to replace a parity disk.

What parity swap does, is copy parity to the new larger disk, then rebuild the failed data disk onto the old parity disk.

Parity swap is one of those phrases that automatically gets converted to a link into the documentation, so you can just follow the link for more details.

If you are ever unsure how to proceed in this or any other situation, please ask for help on the forum. Many ask for help after they have already made things worse.

Thanks trurl for your help and the explanation - i will read the docs carefully 👍

Edited January 31Jan 31 by Zonediver

Another option you can take is to preemptively replace the parity drive with a larger one, then put the removed drive in a drawer as a cold spare. You then won't be worrying and scurrying when you have a drive fail.