OSPF interfaces

For i5/OS, an OSPF interface is an Internet address that represents a logical TCP/IP connection that is associated with an existing i5/OS line description. The line description is configured as an OSPF interface.

Use the ADDOSPFIFC command to set the different parameters needed by the OMPROUTED server to identify an interface as a usable OSPF routing interface. For i5/OS, the interface identifier is an IPv4 or IPv6 address.

OSPF uses multicast functions when interfaces are attached to broadcast networks, such as Ethernet. For all OSPF routers, these interfaces are joined to multicast address 224.0.0.5. Only the packets that are destined for the 224.0.0.5 IP address are received by interfaces that are joined to the multicast IP address. IPv6 uses ff02::5 for the multicast address.
Note: Do not define neighbors on nonbroadcast or multicast-capable media because the OMPROUTED server communicates OSPF information only to those neighbors that are defined and cannot form adjacencies with any additional neighbors.

To identify i5/OS TCP/IP interfaces that are valid OSPF interfaces, use NETSTAT OPTION(*IFC) for IPv4, or use NETSTAT OPTION(*IFC6) for IPv6. If multiple OSPF interface identifiers that belong to a common subnet are added to an OSPF configuration, only one interface actually exchanges OSPF information.