Dear All,

I have 1 Exchange Server 2003 and 2 Exchange server 2010 (DAG and CAS array set and working)

Email routing ;

Biderectional Roting group is taking there for mail flow between Exchange 2003 and Exchange 2010.

There are other connectors on Legacy Exchange server those are

Internal - This connector is created for mailflow between our other postfix server and Legacy server
External - This connector is created for mailflow between sending and receiving to external domains

my questions is ,

I am in a process of moving users to new server and will finish soon.

at some point need to remove the Legacy Server in that case what I need to do for connectors on legac

Take a look at this link. Gives you a step by step list of things to do to remove the last legacy exchange 2003 server

https://technet.microsoft.com/en-us/library/gg576862(v=exchg.141).aspx