How to use Systems Management Server 2.0 through a firewall

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One way of using Systems Management Server through a firewall is to configure the firewalling or proxy server to allow standard and (MS) RPC port traffic to pass.
More information

Systems Management Server UDP Information

When NetBIOS over TCP/IP is selected for Systems Management Server Remote Control, the system uses the following ports:
   Port 137 - name resolution   Port 138 - messaging (sending the screen image)   Port 139 - client sessions				

When NetBIOS over NWLink is used, the router must forward Type 20 packets (the packets that provide NetBIOS support).

Microsoft Windows NT UDP Information

The following list contains the core UDP ports that Windows NT uses and their function:
   DNS                 udp         53   DHCP                udp         67   RPC                 TCP        135   WINS                udp        137   NetBIOS datagrams   udp        138   NetBIOS datagrams   tcp        139   NetBIOS sessions    TCP        139				
To list established connections, type netstat -a from a command prompt. This returns additional UDP ports that a computer running Windows NT Server or Windows NT Workstation is using beyond the core, due to additional services or applications installed on the Windows NT system.

Microsoft SQL Server UDP Information

If you are using TCP/IP Net-Library, enable port 1433 on the firewall. Usethe HOSTS file or an advanced connection string for host name resolution.

If you are using Named Pipes over TCP/IP, enable port 139 for NetBIOS functions. UDP ports 137 and 138 can be enabled for NetBIOS name resolution using b-node broadcast, but this is not recommended. Instead, a WINS server or LMHOSTS file should be used.

When SQL Server 6.x is configured to listen on TCP/IP, it uses TCP (not UDP) port 1433 by default. This port can be configured by running SQL Server Setup on the server and clicking the Change Network Support option. If the default port 1433 is used, the client Net-Library works by default. If a custom port number is used, the client needs to specify that port in the DSN.

Security Notes

For added security, using IP filters with your firewall server can be configured to allow only "registered" addresses use of the ports. There are certain security concerns created by enabling specific ports on a proxying or firewalling server. For additional information about these concerns, visit

Another method of providing Systems Management Server site, client, and administrative communication through a firewall could be to use the Systems Management Server RAS Sender with a Point to Point Tunneling Protocol (PPTP; TCP port 1723) client and server to configure which port is used for initializing the session, then allow that specific port to be open on the firewall server.

Remote Tools:

For more information about remote tools, click the following article numbers to view the articles in the Microsoft Knowledge Base:
167128 Network ports used by remote Helpdesk functions

256884 TCP and UDP ports used by remote control have changed in SP2

Other Related Information

For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
826852 Ports that Systems Management Server 2003 uses to communicate through a firewall or through a proxy server
prodsms netbt

Article ID: 200898 - Last Review: 10/26/2013 02:44:00 - Revision: 6.0

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