My customer attempted to run snapmirror compression between 7.3.2 systems and after some digging we discovered the compressions didn't work due to the lack of mulitple connections as outlined in this KB: https://now.netapp.com/Knowledgebase/solutionarea.asp?id=kb56448
Customer is asking why compression needs two connections and I could not find a clear answer. What parts of the compression process require two connections, and how is it possible to still have a functioning snapmirror relationship (without compression) with only one connection?
It requires that you set up a named connection. That "multi" connection can be a single set of IPs (i.e. you can have a multi connection with only 1 pair).
It's confusing I know, but you are not required to have multiple pairs.