Moving the System Dataset?

[TAC]

I currently have a 'Data' pool (z1) and a 'Data1' pool (z2) on my system. My goal is to move all my data over to 'Data1', add 3 drives to the 'Data' pool to convert it to Z2, and then combine both pools into a single Dataset. Not sure if I have that terminology right, but I'm sure you get the idea.

My question is after I move all my data over to the 'Data1' pool and before I trash the 'Data' pool, I assume I have to change the System Dataset from 'Data' to 'Data1' under the System tab.

 

[kdragon75]

That would be advisable but not the end of the world or your NAS by any means. Keep in mind this process will leave your vdevs totally unbalanced. If your expecting a performance gain by having two vdevs in your pool, you may not see it as zfs will favor the empty vdev until there "balanced". Even then the old data will still be unbalanced. The data would have to be removed and readded to the clean pool for perfect balance.

What your doing is perfectly acceptable, just a heads up.

 

[TAC]

Currently with my two zpools, 'Data' zpool (VDev RAID-Z1 3 drives) and the 'Data1' zpool (VDev RAID-Z2 6 drives) I'm filling one up while there is room on the other which is kind of a PITA.

I figure trashing the current 'Data' zpool and adding 3 HDs to making it a VDev RAID-Z2 (6 drives) I could then add this Vdev to the 'Data1' zpool and not have to worry about what files go where. With the two RAID-2 VDevs in the single 'Data1' zpool I shouldn't have to worry too much about data loss. I do realize if either VDev fails I'm screwed.

Inside of my new single zpool, what is the issue if there is more data in one of the VDevs than the other? As time goes on will FreeNAS slowly balance the data between the VDevs? If there are benefits I could copy some data off the server and then back if FreeNAS will 'balance' things.

 

[TAC]

My main question is with FreeNAS showing my current System Dataset on zpool 'Data' is it as simple as just changing this to 'Data1' under the System tab?

 

[kdragon75]

what is the issue if there is more data in one of the VDevs than the other?

Its all performance. If the data is only on one vdev, you get one vdev of performance. the same applies to new data being written as zfs will attempt to "balance" the used space on each vdev. ZFS will not re-balance old data.

 

[kdragon75]

My main question is with FreeNAS showing my current System Dataset on zpool 'Data' is it as simple as just changing this to 'Data1' under the System tab?

Yep.