The xmim_server –p flag controls the RPC program number used by the server. This option is commonly called the server’s port. This argument to the server allows multiple independent servers to operate on a single server. Each server registers a different RPC program number relative to the given “port” number. All of the TCP and UDP ports are assigned dynamically. Clients get the proper port number for a server by using the portmapper service of the OS.

Port number assignments at or below 128 will continue to provide the RPC service via the portmappper on a dynamic port. Port number assignments greater than 128 will be manually assigned ports. Generally, this is referred to as operating with “well known ports”.

Manually assigned well known ports must be assigned in the range 1056 – 12800. Each server must be assigned on an even multiple of 32. The server will utilize all of the ports in that range for the master and the slave servers. For example, the xmim_server can be started on port 8800 (275*32). The assignments will be:

8800 – xmim_server
8801 – xmim_slave_server updates slave
8802 – xmim_slave_Server rtd update slave
8802 – reserved
8804 – xmim_slave_server port 0
8805 – xmim_slave_server port 1
…
8831 – xmim_slave_server port 28

It is rare to have as many as 28 slave servers associated with a master instance. As many slaves as is necessary can be assigned as along as the port assignments do not overlap.

If other programs or services allocate the ports, then the programs will not operate and the server instance will not function.