Migrating from Nexenta to FreeNAS

[BigT]

I built a new FreeNAS to replace my old Nexenta, and I want to get my data over to the new zpool. The old zpool is a single 3 disk raidz1 vdev, and the new pool is a 6 disk raidz2.

So assuming I connect those three drives up in my new FreeNAS, and FreeNAS can import that pool, is there an easy way to migrate that data from the old zpool to my new one? It's a lot of data, and it would take a week to send it over the network.

 

[INCSlayer]

rsync should do the job i think

 

[depasseg]

ZFS replication. Can you physically attached the drives from the old pool to the system with the new pool? If so, just do a local (CLI) zfs send | zfs receive. If not, you'll have to use ZFS over SSH.

 

[BigT]

@INCSlayer You can set srync up between the pools on the nas itself?

@depasseg I did some searching on that, but I'm a little shaky on it. I get the process:

1. Create final source snapshot:
zfs snapshot -r Data2/Storage@copy

2. Copy the data:
zfs send -Rv Data2/Storage@copy | zfs receive -F Data1/Storage

3. Delete created snapshots:
zfs destroy -r Data1/Storage@copy ; zfs destroy -r Data2/Storage@copy

So is that zfs send -Rv [source pool]/[source dataset] | zfs recieve -F [target pool]/[target dataset]?

I'm also a little curious about how much I need to worry about with regard to the attributes of the dataset. Do I need to dig up UID's and GID's on the nexenta dataset before I go messing with it? Are there any other attributes I should pay special attention to?

 

[Robert Trevellyan]

You can set srync up between the pools on the nas itself?

rsync can do anything cp can do.

ZFS replication

Ideally yes, but you may run into ZFS pool compatibility issues (feature flags etc).

 

[BigT]

Yeah, I know what rsync is... buy I am asking if I can do the rsync between the pools on the NAS without having to have the data go over the network. If I can, then that seems like the better solution as it would keep me from having to worry about my super-old datastores.

 

[Robert Trevellyan]

I am asking if I can do the rsync between the pools on the NAS without having to have the data go over the network.

Yes, using the CLI. The point of my comment was to say that rsync can indeed be used for a local (non-network) copy operation.

 

[BigT]

Hah! Well I am the dense one, aren't I..

I instinctively thought I would not be able to see actual files on the BSD side, but logging into the box I can see I was a moron. Too many years of dealing with block storage I guess. Yeah, I am betting that would be the most sensible option.

Thanks for the responses, guys, all very useful information!

 

[Fei]

Hi @BigT

I use zfs replication backup Nexenta data to Freenas pool , so you can use zfs replication migrate your data.