RouterID statement

Use the RouterID statement as an alternative to specifying the RouterID parameter on the OSPF configuration statement. See OSPF statement for the statement descriptions. The following concepts apply to the RouterID statement:

• If the RouterID statement is specified, the value configured is used as the OSPF router ID. This value must be one of the OSPF interface IP addresses that is configured for the stack.

  Rule: Loopback and reserved 0.0.0.0 addresses are not valid OSPF interface IP addresses.

• If the router ID is not configured, one of the OSPF interface addresses will be used as the OSPF router ID, provided that the interface exists in the TCPIP profile and matches the corresponding OSPF interface statement in the OMPROUTE configuration file at startup.

  Result: When OMPROUTE has to assign the router ID, it does not use dynamic VIPA IP addresses. This avoidance of dynamic VIPA IP addresses cannot be guaranteed; for example, if dynamic VIPAs are the only active OSPF interfaces when OMPROUTE chooses the router ID, then one of them will be chosen.

  Guideline: Because dynamic VIPAs (DVIPAs) can move between z/OS® hosts, the router ID should be a physical interface or a static VIPA, not a dynamic VIPA address. To ensure an appropriate router ID, specify the router ID to OMPROUTE.