Expand AlwaysOn High Availability > Expand Availability Groups >Expand Availability Groups Name. Right click Availability Replica.
Click Next.
Click Add Replica…
Click Connect All…
Input the instance name of your new replica. Click Connect.
Change ‘Readable Secondary’ to Yes. But if you don’t want your secondary replica to be readable, then just accept the default ‘No’.
Click Endpoints Tab just to verify that the new endpoint has been created.
Go to Backup Preference tab. I just indicated ‘20’ under Backup Priority for the new Replica. We already have an existing secondary Replica already taking the DB backups.
Choose Join Only because I already took a full backup of the primary database and restored it to the new replica WITH NORECOVERY option.
Validation
Verify Database Synchronization.
