Windows Server Fail-over Clustering / SQL Cluster Firewall Access Rules

Windows Server Clustering
TCP/UDP Port Description
TCP/UDP 53 User & Computer Authentication [DNS]
TCP/UDP 88 User & Computer Authentication [Kerberos]
UDP 123 Windows Time [NTP]
TCP 135 Cluster DCOM Traffic [RPC, EPM]
UDP 137 User & Computer Authentication [NetLogon, NetBIOS]
UDP 138 DSF, Group Policy [DFSN, NetLogon, NetBIOS Datagram Service]
TCP 139 DSF, Group Policy [DFSN, NetLogon, NetBIOS Datagram Service]
TCP/UDP 162 SNMP Traps
TCP/UDP 389 User & Computer Authentication [LDAP]
TCP/UDP 445 User & Computer Authentication [SMB, SMB2, CIFS]
TCP/UDP 464 User & Computer Authentication [Kerberos Change/Set Password]
TCP 636 User & Computer Authentication [LDAP SSL]
TCP 3268 Microsoft Global Catalog
TCP 3269 Microsoft Global Catalog [SSL]
TCP/UDP 3343 Cluster Network Communication
TCP 5985 WinRM 2.0 [Remote PowerShell]
TCP 5986 WinRM 2.0 HTTPS [Remote PowerShell SECURE]
TCP/UDP 49152-65535 Dynamic TCP/UDP [CAN BE CHANGED]

SQL Server 
TCP/UDP Port Description
TCP 1433 SQL Server/Availability Group Listener [CAN BE CHANGED]
UDP 1434 SQL Server Browser
UDP 2382 SQL Server Analysis Services Browser
TCP 2383 SQL Server Analysis Services Listener
TCP 5022 SQL Server DBM/AG Endpoint [CAN BE CHANGED]
UDP 49152-65535 Dynamic TCP/UDP [CAN BE CHANGED]

Active Directory Traffic
Source IP Range : Server’s IP Range
Destination IP Range [Active Directory Servers]
TCP Ports 53,88,389,464,636,3268,3269
UDP Ports 53,88,389,464

Windows Server Fail-over Clustering Traffic
TCP Ports 135,139,445,1433,2383,3343,5022,5985,5986
UDP Ports 137,138,445,1434,2382,3343,49152-65535

Windows Time Traffic
TCP Ports N/A
UDP Ports 123

Client SQL Server Access Traffic
TCP Ports 1433,2383 (If default port used)
UDP Ports 1434,2382

For a comprehensive list of Services and their associated network port numbers, please refer the Microsoft Official Guide

[source: Microsoft]

Troubleshooting Windows Fail-over Clusters and CSV

  • Generating the comprehensive Cluster Diagnostic Report;


The above command Gets diagnostics for a cluster a cluster that contains VMs and produces a zip file containing the data.


PS C:\> Get-ClusterDiagnosticInfo -WriteToPath “C:\Users\MyUser\HealthTest\”

  • This cmdlet enables you to view the state of your CSV. Understanding the state of your CSV is useful in troubleshooting failures as well as optimizing the performance of your CSV.


The above command is really helpful when it comes to issues with the Cluster Shared Volumes. With this we can easily isolate the issue among the WSFC & Storage System. for more information….. 

[source: Microsoft]