14-6 Riverstone Networks RS Switch Router User Guide Release 8.0
Configuring OSPF Interfaces OSPF Configuration Guide
14.6 CONFIGURING OSPF INTERFACES
To configure an interface for OSPF, first configure an IP interface using the interface create command, then add
the interface to an OSPF area. To add an IP interface to an area enter the following command in Configure mode:
When adding the interface to an area, you have the option of specifying the interface type. The Riverstone RS Switch
Router can run OSPF over a variety of physical connections: serial connections, LAN interfaces, ATM, or Frame
Relay. The OSPF configuration supports four different types of interfaces.
•LAN. An example of a LAN interface is an Ethernet. The RS will use multicast packets on LAN
interfaces to reach other OSPF routers. By default, an IP interface attached to a VLAN that contains
LAN ports is treated as an OSPF broadcast network. To add this type of interface to an area, use the
type broadcast option with the ospf add interface command.
•Point-to-Point. A point-to-point interface can be a serial line using PPP. By default, an IP interface
associated with a serial line that is using PPP is treated as an OSPF point-to-point network. For
additional information on configuring this type of interface, refer to Section14.6.3, "Configuring
Interfaces for Point-to-Point Networks."
•Non-Broadcast Multiple Access (NBMA). An example of an NBMA network is a fully-meshed
Frame Relay or ATM network with virtual circuits. To add this type of interface, use the type
non-broadcast option of the ospf add interface command. For additional information on
configuring this type of interface, refer to Section1 4.6.1, "Configuring Interfaces for NBMA
Networks."
•Point-to-Multipoint (PMP). Point-to-multipoint connectivity is used when the network does not
provide full connectivity to all routers in the network. To add this type of interface, use the type
point-to-multipoint option of the ospf add interface command. For additional
information on configuring this type of interface, refer to Section14.6.2, "Configuring Interfaces for
Point-to-Multipoint Networks."

14.6.1 Configuring Interfaces for NBMA Networks

Because there is no general multicast for these networks, each neighboring router that is reachable over the NBMA
network must be specified, so that routers can poll each other. The RS unicasts packets to other routers in the NBMA
network.
To specify a neighboring router that is reachable over the NBMA network, enter the following command in Configure
mode:
Add an interface to an OSPF area. ospf add interface <name-or-IPaddr>
to-area <area-addr> |backbone
[type broadcast|non-broadcast|
point-to-multipoint]
Specify an OSPF NBMA neighbor. ospf add nbma-neighbor <hostname-or-IPaddr>
to-interface <name-or-IPaddr> [eligible]