Can I remove a drive from a mirror and extend the pools size

TrueNAS General
1

Hi all,

I have a very basic setup for running jellyfin and some acompanying rrs

When I did my intial setup for my data , I decided to use my 2 x 1tb drives as a simple mirror.

I have very quickly run out of space and my case only has space for 3 drives. Can I remove one of my drives from the mirror and make it increase overall space or will that involve starting again with my data?

these are my only 1tb drives (i have a bunch of 500gb and smaller not installed)

Cheers

2

You can “detach” a drive from a mirror, which will downgrade it to a single drive stripe.

Then you can insert a larger drive and attach it to the mirror. TrueNAS calls this “Extend” in the GUI for some weird reason.

Repeat with the other drive.

Once your mirror has been upgraded to larger drives, choose the “Expand” option in the pool to increase its capacity.

:warning: Be careful when dealing with drive detachments, since you will temporarily lose redundancy during this operation.

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Thanks, that does make sense!

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Don’t accidentally add a new vdev. It’s an easy mistake to make.

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I missed this part, since I thought one of those 3 drives is your boot drive.

If you have space for 3 data drives, then you can “Extend” the mirror with an additional large drive before detaching anything. This will always keep your pool in a redundant state.

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Ah yes sorry I should have said. My boot drive is a seperate SDD that isnt using one of the 3 slots. I do indeed have a free HDD slot and hardware ready to go so I will use your second example, thank you.