It is possible to preserve snapshots and migrate data, but it's tedious at best and unpractical at worst, it just depends on your data.
You can use ndmpcopy or qtree SnapMirror (I prefer QSM if you have it). But basically you start with the oldest snapshot you want to keep. Migrate that snapshot for each qtree you want to migrate (or I suppose you can just do the volume if you are doing ndmpcopy). Then take a local snapshot on the destination flex vol (probably with the same name).
Repeat this process with each snapshot you want to preserve. Basically,
I think I have the idea but let me repeat it. Let's assume that my volume, call it, vol2, has two filesystems: A and .snapshot. Under .snapshot, I have three snapshots: oldest, old, latest.
I start out by ndmpcopy the oldest: ndmpcopy -da -sa source:/vol/vol2/.snapshot/oldest/A destination/vol/vol2
Then, I take a snapshot on the destination: snap create oldest
Next, I do old: ndmpcopy -da -sa source:/vol/vol2/.snapshot/old/A destination:/vol/vol2 snap create old
Finally, latest: ndmpcopy -da -sa source:/vol/vol2/.snapshot/latest/A destination:/vol/vol2 snap create latest.
Then, I proceed to do a level 0 ndmpcopy of vol2 ndmpcopy -da -sa source:/vol/vol2 destination:/vol/vol2
Michael Homa Operating Systems Support and Database Group Academic Computing and Communication Center University of Illinois at Chicago email: mhoma@uic.edu
This may eat up a lot of disk space and take a long time.
I suggest doing a level 0 ndmpcopy (full dump) of the oldest snapshot and then do incremental ndmpcopy of the newer snapshots. That way you only copy files that have changed rather than copying everything.
Steve Losen scl@virginia.edu phone: 434-924-0640
University of Virginia ITC Unix Support