Advanced Domino® TCP/IP configurations

Domino® servers and partitioned Domino® servers can have multiple NICs (network interface cards), each with its own IP address.

A single IBM® Domino® server can have multiple IP addresses if you use multiple NICs that each offer an address, or if one NIC offers multiple addresses. Having multiple IP addresses allows the server to listen for connections at more than one instance of the TCP port assigned to NRPC (1352) or at TCP ports that are assigned to other services such as LDAP or HTTP.

Multiple IP addresses and NICs on a Domino® server

Set up a Domino® server with multiple IP addresses, each with its own NIC, if you want to accomplish the following tasks:

  • Split the client load for better performance
  • Split client-to-server access from server-to-server communication
  • Set up mail routing, replication, or cluster replication on an alternate path (private network)
  • Partition a Domino® server so that more than one partition offers the same Internet service (SMTP, POP3, IMAP, LDAP, or HTTP).
  • Allow access to the Domino® server via a TCP/IP firewall system over a different network segment, a configuration known as a demilitarized zone (DMZ)
  • Use a Domino® pass-through server as an application proxy
  • Provide network/server failover, used in mission-critical resource access
  • Set up alternate window and/or maximum transmission unit (MTU) settings for satellite uplink and downlink connections isolated from local access connections

For a configuration with multiple IP addresses, you must bind each listening port to the appropriate IP address to ensure that each TCP service receives the network connections intended for it.

Note: A configuration with multiple NICs does not increase the number of Domino® sessions you can have on a server. In TCP/IP, machine capacity depends on processors and memory.

Multiple IP addresses with one NIC

Reasons to use one NIC to serve multiple IP addresses include:

  • Isolating local versus WAN IBM® Notes® named networks so local users can see only local Domino® servers
  • When setting up redundant WAN path connections for server to server access
  • When the use of a different TCP/IP port map is needed for firewall connections
  • When offering HTTP services to a different group than NRPC connections

For a configuration with multiple addresses and one NIC, you must configure the TCP/IP stack and bind each listening port to an IP address.