Darren, You mentioned problems with snapmirror with 7G. Could you elaborate? Thanks.
I can't provide many details. I was only called in to assist with an upgrade on an 810c cluster to 7.0.1 and to set up some qtree level snapmirrors.
The client later said he'd had some problems with them (hangs, panics when trying to quiesce one of the mirrors) and that support said it was a known problem, suggested downgrading to 6.5, and I could I help him perform the downgrade.
I don't know much about the original problems, but when we started the downgrade, there were some snapmirror "bits" that I couldn't get rid of. I was trying to "break" them on the destination, but it said they were already broken. But it still had a snapshot in use that couldn't be deleted. Support helped us clean it up (mainly just cleaning up the mirror.conf file) and I was able to complete the downrev.
Sorry I don't have more details.