Cache Pool SSD Upgrade / Replacement Process

[PitRejection2359]

Hi Fellow Unraiders,

 

I have a cache pool with 1 x 500GB drive and 3 x 240 GB drives, all SSDs and in btrfs RAID 1 mirror configuration with 610 GB usable space across all 4 drives. One of the 240 GB drives is starting to fail with a bunch of SMART errors, so I've bought a second 500GB SSD to replace / upgrade it.

 

I've done a bit of searching and there appears to be a couple of ways of manually moving / backing up the files on the cache (app data, VM, docker, etc - everything else is already automatically moved to the main array), but given this is RAID 1, can I simply do the following:

 

1. Stop the array (and cache).
2. Add the new SSD to the cache as a 5th disk in the cache.
3. Start the array, and let it a sync (not sure if this requires a manual start somehow possibly with mover, or if it would happen automatically).
4. Stop the array when complete and remove the failing drive.
5. Start the array and let it sync again.

 

Obviously there's some risk while the data is not actually mirrored, but other than that small risk, would the above process work? Or would it be possible to reduce the steps further by removing and replacing the 2 SSDs both at the same time when shut down - would the sync pick that back up afterwards and re-duplicate the data onto the new drive?

 

Any help / tips appreciated - thanks!

[JorgeB]

You can do a direct device replacement if you are on latest v6.10, it was broken on v6.9.

 

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/?do=findComment&comment=480419

 

 

[PitRejection2359]

34 minutes ago, JorgeB said:

You can do a direct device replacement if you are on latest v6.10, it was broken on v6.9.

 

https://forums.unraid.net/topic/46802-faq-for-unraid-v6/?do=findComment&comment=480419

 

 

I'm still on 6.9, but maybe this is a good opportunity / reason to upgrade! Thank you.