Snapshots still work with CloudPools.  This means you won't see your space savings for an archived file on the cluster until the last snapshot containing that file.  After that, the stubs will be preserved in snapshots moving forward, but the clients cannot tell the difference so Previous Versions will still work as long as the stub is in a snapshot on the Isilon.

And of course it's really no big deal, because snapshots are recently changed versions, let's say at max usually 30 days.  Archive is at the other end of the spectrum, data that hasn't been used in 3 years, 5 years, etc.  So as long as you're not too aggressive in the Policies for CloudPools, and don't keep snapshots too long, then there likely won't be much overlap of data that is actively changing. Therefore it likely won't consume any space in the shadow stores used to hold the changed blocks from the snaps.

~Chris

Agree.  95% of the time, this is not a problem as most snaps are expired in a matter of weeks (on the high side).  Every once in a while I run into someone who has snaps retained for a couple of years.  In those rare cases, it's not pretty.