Configuring a partitioned server for one IP address and port mapping

To configure server partitions to share the same IP address and the same NIC, you use port mapping. With port mapping, you assign a unique TCP port number to each server partition and designate one partition to perform port mapping. The port-mapping partition listens on port 1352 and redirects IBM® Notes® and IBM® Domino® connection requests to the other partitions.

About this task

If the port-mapping partition fails, existing sessions on the other partitions remain connected. In most cases, Notes® clients will not be able to open new sessions on any of the partitions. However, because each Notes® client maintains information in memory about recent connections, including those redirected by the port-mapping partition, a client may be able to connect to a partition even when the port-mapping partition is not running. A client or remote server that has a Connection document containing both the IP address and the assigned port can always access the port-mapping partition.

Because the port-mapping partition requires extra system resources, consider dedicating the partition to this task only. To do this, remove all other server tasks, such as mail routing and replication, from the partition's NOTES.INI file.

Port mapping works for NRPC communication only. However, you can use the Server document in the Domino® Directory to configure IMAP, LDAP, and POP3 services and Domino® Web servers to use unique ports for communication. When you do, you must make the port number available to users when they try to connect to the servers.

Note: Because Internet protocols carry a large amount of data, you may encounter I/O bottlenecks if you use a single NIC with too many server partitions. Consider adding additional NICs and isolating the data by protocol.

When you set up port mapping, the port-mapping partition automatically routes NRPC communication requests to the other server partitions.

Note: When setting the NOTES.INI variables for port mapping, do not include a zone in a port mapped address. The zone is only valid locally.


  1. Decide which server partition will perform port mapping.
  2. Choose a unique TCP/IP port number for each server partition on the computer. The port-mapping partition uses the assigned port, 1352. It is best to use port numbers 13520, 13521, 13522, 13523, or 13524 for the additional server partitions.
  3. In the NOTES.INI file of the port-mapping partition, include one line for the port-mapping partition and one line for each of the other partitions. For the port-mapping partition, enter:

    where TCPIP is the port name, and IPAddress is the IP address of the port-mapping partition.

    For each of the other partitions, enter:

    TCPIP_PortMappingNN=CN=server_name/O=org,IPaddress:TCP/IP port number

    where TCPIP is the port name, NN is a number between 00 and 04 assigned in ascending sequence, server_name is the server name of the partition, org is the organization name, IPAddress is the shared IP address, and TCP/IP port number is the unique port number you chose for the partition.

    Note: You must assign the numbers for NN in ascending order beginning with 00 and ending with a maximum of 04. If there is a break in the sequence, Domino® ignores the subsequent entries.
  4. In the NOTES.INI file of each of the other partitions, include this line:
    TCPIP_TcpIpAddress=0, IPAddress:IPport_number

    where TCPIP is the port name, IPAddress is the shared IP address, and IPport_number is the unique port number you chose for the partitioned server.

  5. In the Net Address field on the Ports > Notes Network Ports tab in the Server document for each partition, enter the fully qualified domain name -- for example, -- or enter the common server name -- for example, Sales.
  6. Create an IP address entry for the port-mapping partition in the DNS, NIS, or the local hosts file.
  7. Include each partition name as a separate CNAME entry in the DNS, NIS, or the local hosts file.
  8. If you also plan to set up the partitions for IMAP, LDAP, and POP3 services and Web server communication, assign to each protocol a unique port number in the TCP/IP port number field on the appropriate subtabs (Web, Directory, and Mail) on the Ports > Internet Ports tab of the Server document.
    Note: You must make these port numbers available to users when they try to connect to these servers. For example, if you assign port 12080 to the Web server, users must include in the URL in order to connect to the server, unless they have a means to redirect the connection to this port assignment.


The following example shows the lines you add to the NOTES.INI files of the server partitions to set up port mapping for six partitions.

Partition 1 (the port-mapping partition)



Partition 2



Partition 3



Partition 4



Partition 5



Partition 6