I was working with one of my customer. He wanted to change IP/Subnet/AD site for an existing DAG member.
Changing subnet for existing DAG member server.
Change of AD site and IP/Subnet range in your organization.
Exchange 2010 SP1 and later
Windows server 2008 R2 SP1
AD Site: 2+
Example Subnet change from 255.255.0.0/16 to 255.255.252.0/22
DAG networks and multiple subnet deployments:
In the preceding example, even though there are two different subnets in use by the DAG (192.168.1.0 and 10.0.0.0), the DAG is considered a single-subnet DAG because each member uses the same subnet to form the MAPI network. When DAG members use different subnets for the MAPI network, the DAG is referred to as a multi-subnet DAG. In a multi-subnet DAG, the proper subnets are automatically with each DAG network.
To accomplish this we need to perform below steps.