Here's a quick question about snapmirror in the cascade.
If there is a cascaded Snapmirror replication A->B->C and a reverse will happen between A & B, Do I need to quiesce/break the replication between B & C in advance or I can just leave it? Please also mention the reason.
Not a hundred percent sure as to what you're really trying to accomplish, but the simple answer is no you do not have to quiesce/break the replication between B and C prior to reversing A and B because you're not really affecting the relationship from B to C. In effect, you're turning B into the "source" for both A and C.
For example... this is "B" before the reversal (1netapp03 -> 1bon01 -> 5netapp01)...