ZFS cloning ?

[drsgrid]

Is there a way to copy a pool to another machine, i recall seeing something on cloning, but think it might take forever to clone 20T over gigE - is there a best practice/approach for something like this?

 

[mwroobel]

You can use dd to copy from one drive/volume/filesystem to another, but yeah it will take a long time over GigE. If you could connect and mount the array to the first machine via SAS for example, then it would go faster but is MUCH more involved and fraught with peril if something goes wrong. You can read up more here http://www.backuphowto.info/linux-backup-hard-disk-clone-dd but be VERY careful that you specify the rightifand of statements!

 

[s0rce]

you can use zfs send and receive instead of dd, these can be sent over the network via ssh or netcat but it would be faster to attach the drives locally.

 

[Billy_nnn]

You can use ZFS send and receive commands to replicate the contents of one zpool to another (you use it in combination with ssh if the destination zpool is on another system)

As you said though, over gig ethernet it would take some time to replicate 20TB (probably c.3-5 days) - though if you can't connect both pool's drives to the same system at the same time, and you want to copy the pools contents, there's not much in the way of alternatives.
You could use an external SATA drive, if you have one, and then copy the pool over in stages, though that would probably take just as long as over the network, maybe longer!