Does anyone know how to migrate a ZFS zpool from one big LUN to several smaller ones?

We have a 2 TB database mount. Our new Netapp provisioned 4 LUNs of 512 GB. The same total size but not by individual LUN.

On VXVM I could use vxevac and it would move the data to as many LUNs as needed -

vxevac ... big_lun new_1 new_2 new_3 new_4

Or I could build a plex witht he several new LUNs, mirror, sync, break the mirror.

On the Linux/HPUX/AIX LVMs that use logical partitions I could wrote a loop that live migrates the logical partitions one at a time until they had all been moved off the big LUN.

On ZFS "zpool -z database attach old new" does not allow several new devices.

I would very much like to be able to do this as a live migration. I've already migrated the boot points of my local zones live with zpool attach/detach, but that LUN was provisioned explicitly by size.

A trade off I see - If I let Netapp allocate the LUNs it can monitor them all together as a database. I can provision by hand to exact size but then it does not know they form a set.

Have a look to "shadow migration".

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Thanks! According to that document the source needs to be read-only, so it's a "dead migration" rather than a "live migration". Not clear how it's better than shutting down Oracle and doing a move or copy to a new mount point. The copy speed would be similar with a small number of large files.

Did I read it wrong that the source needs to be read-only? If the destination needs to be read-only that at least lets me sync alive then only have the database down time as a cycle not as a copy.

You didn't read it wrong.

The source need indeed to be set in read-only mode. However, the destination will be in read-write mode as soon as you start the shadow migration and all data will be accessible from it.

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