Is there a documented process for converting a single ssd xfs cache drive to a pool? I'd like to add a second ssd for redundancy.

 

I'm thinking that I could add the second ssd to my server, format as btrfs, and then copy all of the contents from the xfs cache to the unassigned btrfs drive. Then switch the cache from the current xfs drive to the btrfs drive, test to make sure it's all working, then reformat the xfs drive to btrfs and add it to the pool. Does that sound like a good plan?

 

Btw, are there any downsides to moving from single xfs to a pool of btrfs?

 

Thanks!

I don't know if a drive formatted btrfs with the third party unassigned devices plugin will mount and be recognized as valid if it's assigned as a cache drive. I think I remember people having issues adding xfs formatted drives as array devices, unraid doesn't recognize the partition setup or something.

 

Back up the contents of your cache drive to an array location, then you can experiment and tell us if it works!

Sounds good, just make sure to back it up, and turn off all your VMs and Dockers, and make sure they don't auto-start.

Following up here as I finally got around to setting up the cache pool.

 

The unassigned devices plugin wasn't working to format the new SSD as btrf, so I just copied the cache contents to a user share (one that doesn't use cache). Then I added the new drive as the only cache drive, formatted as btrf and copied the files back. All was working, so then I added the old xfs ssd back to the cache as a drive in the pool. Everything is working, except I now get a warning message that says, "Your existing Docker image file needs to be recreated due to an issue from an earlier beta of unRAID 6. Failure to do so may result in your docker image suffering corruption at a later time. Please do this NOW!"

 

I'm fairly certain that this warning doesn't apply (at least not as written) but it's a bit annoying. I haven't recreated the image file yet because I hate to mess with things that are working. I know it's easy (I've had to do it in the past) but I'm still hesitant...

 

Anyway, except for this warning the conversion went very smoothly.

 

 

No, it does apply. Make sure you re-set the NCOW no copy on write attribute on your docker image.