On 2011 Oct 20, at 0:42 , Jeff Cleverley wrote:
We have a NearStore at another site. It started life as a 7.3.2 system and was later upgraded to 8.01. When it was 7x, they used all the disks except hot spares in existing aggregates. When they upgraded to 8.x and got more shelves, they used all the new disks and put them into a 64 bit, 30 TB aggregate.
They are now running out of space in the 32 bit aggregate and need to move something to the 64 bit aggregate. They do not have a SM license and it appears everything else that can migrate snapshots as well as the data will not work between mixed bit aggregates.
Ah... I guess the best solution would be to just use SnapMirror, as it can convert from 32 to 64 bit (in 8.1). If you explain your situation to a netapp sales rep, you may be able to get a temporary snapmirror license, just so you can convert the data.
If you have enough free space available in the 30T 64 bit volume, I'd move all data to the other aggregate (which is very convenient with 'snapmirror migrate', I might add), and then ditch the old 32 bit aggr, and add the disks to the existing 64 bit aggr.
The need to add at least 1 disk into the 32 bit aggregate to enable it to convert to 64 bit requires using one of the hot spares. Obviously we can't pull that disk back out of the aggregate. Adding one disk to a raid group will create a hot disk unless you reallocate all of the volumes in the aggregate. That is why it would be more convenient not to have to add drives in order to convert the bit level.
If they did have more drives they could add enough disks to make a reasonable raid group and convert it. Unfortunately they don't have enough left over disks.
There was another remark regarding compressions only available in 64 bit aggrs... I wasn't aware of that. That seems like a valid reason to want to convert an existing 32 bits aggr.