Upgrading from single 10TB parity to dual 18TB parity.

[datruedave]

OK, so I bought a couple of 18TB drives, and I was going to use one of them to upgrade my parity disk and the other to upgrade a data disk, but after a recent scare where I had two missing disks (turns out it was a known issue with WD drives and SATA power - both drives are fine), I think I want to move to dual parity.  I searched the forums and wasn't able to find anything on this.  Probably because I suck at searching.

 

Should I replace the single parity and let it rebuild first, or is it possible (and safe) to throw both drives in there at the same time and rebuild them both at the same time? 

[jmztaylor]

Parity Swap should work for you

[datruedave]

49 minutes ago, jmztaylor said:

Parity Swap should work for you

Hmmm...  Forgive me as I'm slow sometimes.  How would that apply to my situation? 

I don't really want to touch the data drives until after I've upgraded my parity drive(s).  I was just wondering if I had to upgrade my existing single parity drive first, and then add the second parity drive, or if I could rebuild both at the same time.
 

After I've upgraded my parity, I do plan on replacing a data drive with the old parity, and then trying to reformat the disks that are still ReiserFS when I'm able to figure that out.  But parity first before I touch any data disks.

[itimpi]

11 minutes ago, datruedave said:

Hmmm...  Forgive me as I'm slow sometimes.  How would that apply to my situation? 

I don't really want to touch the data drives until after I've upgraded my parity drive(s).  I was just wondering if I had to upgrade my existing single parity drive first, and then add the second parity drive, or if I could rebuild both at the same time.
 

After I've upgraded my parity, I do plan on replacing a data drive with the old parity, and then trying to reformat the disks that are still ReiserFS when I'm able to figure that out.  But parity first before I touch any data disks.

My suggestion would be to first add the parity2 drive and build parity on that and then replace the parity1 drive.   That means that you have parity protection during the process.  

 

In theory you could do both at the same time but if a data drive failed while doing that you could end up with data loss.

[datruedave]

On 6/4/2022 at 4:08 PM, itimpi said:

My suggestion would be to first add the parity2 drive and build parity on that and then replace the parity1 drive.   That means that you have parity protection during the process.  

 

In theory you could do both at the same time but if a data drive failed while doing that you could end up with data loss.

Thanks.  I thought maybe if I rebuilt both, it would be the same as rebuilding single parity in terms of protection, but thinking about it further, I see that dual parity is completely different from single parity.

I've actually decided to stick with single parity until I'm done reformatting my ReiserFS drives.  I think having a much larger data drive will make that a lot easier.

 

Thank you again!