What are the port requirements for Distributed Availability Group (DAG)?

Question

I plan to implement DAG with below topology (winserver 2019, sql server 2019):

DC A:

1. Primary DC
2. Secondary DC
3. Quorum witness

DC B:

1. Primary DRC
2. Secondary DRC
3. Quorum witness

Notes:

1. Seperated replication and access IP

Question:

1. What is all of the complete port requirement for Distributed Availability Group (DAG), including wsfc, etc..
2. It's description on why those port need to be allowed.
3. Which port on VM that need to be allowed? (ex: Primary DC/Secondary DC/Primary DRC/Secondary DRC/Quorum witness DC/Quorum witness DRC)
4. Please attach with microsoft official documentation.

Answer 1

Hi @ Bayu Aji Setyawan

I did not find the MS document for port requirement of DAG, but you can refer to MS document Configure a distributed Always On availability group, port 5022 is listed.

Searched this information online, please check.

For SQL Server:

• TCP 1433: This is the default port for SQL Server. If you've configured a different port for your SQL Server instance, make sure that port is open.
• TCP 5022: This port is used for database mirroring endpoints, which are crucial for communication between the primary and secondary replicas in the DAG.

For Windows Server Failover Clustering (WSFC):

• UDP 3343: Used for cluster service communication.
• TCP 135: Used for RPC (Remote Procedure Call) communication.
• TCP 445: Used for SMB (Server Message Block) communication.
• TCP 139: Used for NetBIOS session service.
• UDP 137 and 138: Used for NetBIOS name resolution and datagram service.

For Availability Group Listener:

• TCP 1433: This is the default port for the availability group listener. If you've configured a different port for the listener, make sure that port is open.

Additional Ports:

• TCP 2383: Used for SQL Server Analysis Services.
• TCP 2382: Used for SQL Server Browser service.

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