"... the port used for DAG log shipping and seeding, which is 64327 by default. Looking back at Exchange 2007 this is good; the port is static and DAGs use regular TCP, where CCR/SCR in Exchange 2007 uses 445 for log shipping (over SMB) and a dynamic port for seeding. And if it’s two things some network people hate it’s SMB and dynamic ports. On the other hand, 64327 in the dynamic range defined by IANA; according to IANA dynamic ports cannot be registered (claimed).
Fortunately, the port can be changed when required. To change the port for a DAG use the Set-DatabaseAvailabilityGroup cmdlet with the ReplicationPort parameter like this, where
can be any number between 1 and 65535:
Set-DatabaseAvailabilityGroup -Identity DAGID -ReplicationPort
Note that Exchange will not adjust the Windows Firewall rules accordingly, so you need to create a firewall exception on each DAG member to make replication work. Even better, you should do this before changing the DAG port to prevent interrupting the replication longer than necessary."
For a full list of the ports used by Exchange 2010, see the Exchange Network Port Reference.