i may have shot myself in the foot by adding a dedup device to my pool without understanding what i was doing. now i can’t seem to remove it, even though it’s unused. (no data set has deduplication enabled.) my configuration looks like so: # zpool list -v data …

Unfortunately, you can’t remove a dedup VDEV from a RAIDz2.

even though it isn’t used? bummer. hypothetical: what happens to the pool if that device fails?

You lose the pool. I am not aware of any way of going back unless you made a checkpoint. That might be able to help. But if you didn’t manually make one (in the CLI) there won’t be one to go back to.

well damn, i’ve really shot myself in the foot here, then. i guess i’ll have to back up my data to some other storage, delete the pool, and recreate everything from scratch. that’s gonna hurt… i’ll have to go searching for any way to back up the NAS configuration that would not also back up the poo…

Sorry, I am not aware of a way to “save” the dataset configuration specifically. There’s the TrueNAS config of course, but that’s not quite what you’re after here. While I haven’t tried it myself - shares appear to reference data using basic paths. So presumably you could disable the shares before …

There really really really need to be some “You are about to add a DEDUP vDev to your ‘data’ pool. THIS WILL BE PERMANENT AND CANNOT LATER BE REMOVED. Are you sure?” messages in TrueNAS. @kris @honeybadger

so, backing up my data to a different device then deleting / recreating the pool seems to be the thing to do. of course, i don’t have another five terabytes of networked RAID just lying around unused. but i DO have a USB disk large enough, and for a temporary procedure it’d do. now how do i get Tr…

You don’t. You connect it to a client and transfer the data across the network.

But if you could, a locally connected 12TB USB disk with a ZFS pool on it could then use replication to copy the data.

Removing a device i shouldn't have added to pool

TrueNAS General

winnielinnie December 25, 2024, 2:50pm 7

Next time make a checkpoint before adding a new vdev to your pool.

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Removing a device i shouldn't have added to pool

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