Jump to content

How to re add a cache drive that had a failed cable?

Go to solution Solved by JorgeB,

Recommended Posts

So a while back i had to remove 1 disk of my 3 drive cache pool because of an issue that was causing write errors for the drive. Since then i've worked out that the drive is fine and that it was an issue with the sas to 4 x sata cable that i was using, i've replaced the cable now. How do i go about re adding the previously removed cache drive back to the cache pool?


Before removing the drive the pool was made up of 3 x 1TB ssds and i think i had it as a mirror (yes that was dumb) and it had a total capacity of 1.5TB. After removing the drive the pool got converted into what i think is just a 2 disk mirror with 1TB of total storage. My goal is to re add the failed drive to go back up to 3 disks total and then i want to convert it into whatever raid will give me 2TB of storage with 1 disk being used for redundancy.


Ideally it would be nice if there is a way to do this while leaving the data in place and not having to move everything to the array and then back onto the cache pool as the cache pool has a lot of tiny files and will probably take a long time to move over and back again

Link to comment

well it's not technically a new device, it's the old device being re added after an extended period of time, will the system just play nice with that or will it try and do something strange as it will recognise it as a previously existing disk in the pool?


Also how hard should it be to convert the pool to a raid 5 after adding the drive back?

Link to comment
  • Solution

It shouldn't matter is it was a previous pool device, it will be wiped first, there will be a "all data on this device will be deleted" when you add it to the pool.


21 minutes ago, nmills3 said:

Also how hard should it be to convert the pool to a raid 5 after adding the drive back?

It's easy, but btrfs raid5/6 is not really recommend, I would recommend using zfs raidz instead, of course that would require that you backup and re-format the pool.

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...