You can add a new member server to a DAG client.
Before You Begin
You must install the Exchange package on each member server using the fully qualified domain name.
From the navigation pane, go to Protect > Applications > Exchange.
The Exchange page appears.
Click an Exchange database.
The Exchange Database page appears.
In the General section, click Edit.
The Edit Exchange Database dialog box appears.
From the Member servers list, select the member server that you want to add, and then click OK.