We have two DAGs (DAG1 and DAG2). DAG1 has been running for a year. We had 2 mailbox servers and 2 CAS/HT servers in Site A and in Site B. We have an MPLS connection between the sites for MAPI and we also have a replication circuit for the replication. We have successfully failed over (on purpose and as a result of failures) with little impact to the users (their outlook said their admin made changes and they closed and reopened and were connected to the mb in Site B).
Now I have built out a second DAG (DAG2) and added 1 mailbox server and 1 CAS/HT server to each site. Shuffled some databases around and basically have DAG1 with 2 mb servers in Site A and 1 in Site B, and DAG2 with 2 mb servers in Site B and 1 in Site A.
My question is can I have DAG2 use the same MAPI and replication subnets as DAG1?