TCP Ports required for NDMP operation

Answer

There are two types of NDMP TCP ports used in Tivoli Storage Manager NDMP operation.

1. NDMP control port :
   Used internally by Tivoli Storage Manager during both backup and restore operations.
   TSM server option: NDMPCONTROLPORT
   Default NDMPCONTROLPORT port: 10000
   
2. NDMP data port :
   Used during NDMP backup operations to a Tivoli Storage Manager native storage pool. The data port is an OS ephemeral port that is acquired at the beginning of NDMP backup operations to a Tivoli Storage Manager native storage pool.
   TSM server option: NDMPPORTRANG
   Default NDMPPORTRANG: 0,0

The default is 0,0 which means that the Tivoli Storage Manager server lets the operating system provide a port (ephemeral port).

A firewall may prevent the NAS file server from contacting the Tivoli Storage Manager server on the acquired data port during NAS backup operations to a native storage pool. If you must modify the data port selected by the Tivoli Storage Manager server, use the following option in the dsmserv.opt file :

NDMPPortrange port_number_low,port_number_high

port_number_low
The low port number from which Tivoli Storage Manager starts to cycle when needing a port number for accepting session from a NAS device for data transfer. The minimum port number value is 1024.

port_number_high

The high port number to which Tivoli Storage Manager can cycle when needing a port number for accepting session from a NAS device for data transfer. The maximum port number value is 32767. The high port number must be the same or larger than the low port number.

Note: port_number_low to port_number_high need to be opened on the firewall.