DOCUMENT:Q258469 12-AUG-2002 [winnt] TITLE :Cluster Service May Not Start After Restricting IP Ports for RPC PRODUCT :Microsoft Windows NT PROD/VER::2000,4.0 OPER/SYS: KEYWORDS:kbenv ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server, Enterprise Edition version 4.0 - Microsoft Windows 2000 Advanced Server - Microsoft Windows 2000 Datacenter Server ------------------------------------------------------------------------------- IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base: Q256986 Description of the Microsoft Windows Registry SYMPTOMS ======== When you restrict the available Internet Protocol (IP) ports that are available for remote procedure call (RPC) dynamic port allocation by adding the DCOM Internet key in the HKEY_LOCAL_MACHINE\Software\Microsoft\RPC registry key, the Cluster service may not start or you may not be able to remotely connect to the Cluster service by using Cluster Administrator. This problem typically occurs if the Cluster nodes are seperated by a firewall. When the Cluster service on a node starts, it first tries to contact one of the other nodes in the Cluster through RPC. CAUSE ===== This behavior can occur when the range of available IP ports that the Cluster service uses to initiate communication through RPCs is too small. The Cluster service relies heavily on RPC to function properly. If there are not enough ports available, the Cluster service cannot communicate. RESOLUTION ========== WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk. To resolve this behavior, make a minimum of 20 ports available in the defined range of available ports. For example, the following registry entry has 20 ports available in the defined port range: HKEY_LOCAL_MACHINE\Software\Microsoft\RPC Ports: REG_MULTI_SZ: 8011-8031 PortsInternetAvailable: REG_SZ: Y UseInternetPorts: REG_SZ: Y MORE INFORMATION ================ It is best to have 50-100 ports available, because many other services use DCOM ports in the dynamic range (1025-65000, everything below 1025 is a pre-defined port). Examples of other services that use dynamic ports include Domain Name System (DNS), Windows Internet Naming Service (WINS), and Microsoft SQL Server. REFERENCES ========== For additional information, click the article number below to view the article in the Microsoft Knowledge Base: Q154596 Configuring RPC Dynamic Port Allocation to Work With Firewall Additional query words: mscs com ====================================================================== Keywords : kbenv Technology : kbWinNTsearch kbWinNT400search kbwin2000AdvServ kbwin2000AdvServSearch kbwin2000DataServ kbwin2000DataServSearch kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400search kbwin2000Search kbWinAdvServSearch kbWinDataServSearch Version : :2000,4.0 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2002.