I'm just curious if i'm missing something.
destination volume is required in both those cmdlets.
Well with svm-dr the command on the CLI is
snapmirror resync vservername: or snapmirror update vservername:
if you try to run
invoke-ncsnapmirrorupdate it will fail b/c there is no destination volume, or if you try a volume you will get it's a member of a constituent.
I know this must be something simple, Anyone?