Specifying a range of port numbers for use in communication processing

The ports to be used for communication between a HiRDB server and a HiRDB client or between HiRDB servers are assigned automatically by the OS. If a large volume of communication occurs, a shortage of ports might interrupt communication processing or might have an adverse effect on the communication processing of other programs. To prevent such problems from occurring, it is possible to specify a range of port numbers to be used by HiRDB for communication processing.

It is not necessary to specify this facility if only a small number of ports will be used for communication processing. This facility is applicable to server-to-server communication, and will not necessarily be applicable to all processes under HiRDB. The port numbers assigned by the OS will be used for communication processing such as the processing of commands.

For the Linux editions of HiRDB, consider whether to specify a range of port numbers. For other OS editions of HiRDB, you do not need to specify a range of port numbers.

Organization of this section: (1) Number of ports used by HiRDB; (2) Specifying a port number range; (3) Notes

It is important to ensure that the port number specified in the pd_registered_port operand do not duplicate any of the following port numbers (if there is a duplication in port numbers, an error might occur and it will not be possible to start HiRDB):

Port number specified in the pd_name_port operand
Port number specified in the pd_service_port operand
Port number specified in the -p option of the pdunit operand
Port numbers registered in /etc/services
Port number specified in the PDCLTRCVPORT operand in the client environment definition (when the HiRDB client resides in the same server machine as the HiRDB server)
Port number being used by another program

If Y, C, or W is specified in the pd_registered_port_check operand, HiRDB checks the port numbers in 4 for any duplications. If N is specified in the pd_registered_port_check operand, HiRDB will not check port numbers, and the HiRDB administrator must make the check for duplicated port numbers.

Hint

In a multi-HiRDB environment, ensure that the range of reserved port numbers for each HiRDB (the range specified in the pd_registered_port operand) does not duplicate any other range of port numbers.
If the system switchover facility is used and multiple units exist on a single server machine, specify the pd_registered_port operand of the unit control information definition instead of the system common definition. Ensure that the range of reserved port numbers for each unit does not duplicate any other range of port numbers.pd_registered_port_level.
You can use operands to specify the target range for the HiRDB reserved port facility. For details, see the manual HiRDB Version 9 System Definition.

9.7 Specifying a range of port numbers for use in communication processing

(1) Number of ports used by HiRDB

(2) Specifying a port number range

(3) Notes