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Cisco ME 3800X and 3600X Switch Software Configuration Guide
OL-23400-01
Chapter 29 Configuring IP Unicast Routing
Configuring OSPF
In this example, the major net is 10.0.0.0. The summary address 10.2.0.0 overrides the autosummary
address of 10.0.0.0 so that 10.2.0.0 is advertised out interface Gigabit Ethernet port 2, and 10.0.0.0 is
not advertised. If the interface is in Layer 2 mode (the default), you must enter a no switchport interface
configuration command before entering the ip address interface configuration command.
Note
If split horizon is enabled, neither autosummary nor interface summary addresses (those configured with
the ip summary-address rip router configuration command) are advertised.
Switch(config)#
router rip
Switch(config-router)#
interface gi0/2
Switch(config-if)#
no switchport
Switch(config-if)#
ip address 10.1.5.1 255.255.255.0
Switch(config-if)#
ip summary-address rip 10.2.0.0 255.255.0.0
Switch(config-if)#
no ip split-horizon
Switch(config-if)#
exit
Switch(config)#
router rip
Switch(config-router)#
network 10.0.0.0
Switch(config-router)#
neighbor 2.2.2.2 peer-group mygroup
Switch(config-router)#
end
Configuring OSPF
Open Shortest Path First (OSPF) is an Interior Gateway Protocol (IGP) designed expressly for IP
networks, supporting IP subnetting and tagging of externally derived routing information. OSPF also
allows packet authentication and uses IP multicast when sending and receiving packets.
This section briefly describes how to configure O SPF. For a complete description of the OSPF
commands, see the “OSPF Commands” chapter of the Cisco IOS IP Command Reference, Volume 2 of
3: Routing Protocols, Release 12.2.
Note
OSPF classifies different media into broadcast, nonbroadcast multiaccess (NBMA), or point-to-point
networks. Broadcast and nonbroadcast networks can also be configured as point-to-multipoint networks.
The switch supports all these network types.
The Cisco implementation conforms to the OSPF Version 2 specifications with these key features:
•
Definition of stub areas is supported.
•
Routes learned through any IP routing protocol can be redistributed into another IP routing protocol.
At the intradomain level, this means that OSPF can import routes learned through EIGRP and RIP.
OSPF routes can also be exported into RIP.
•
Plain text and MD5 authentication among neighboring routers within an area is supported.
•
Configurable routing interface parameters include interface output cost, retransmission interval,
interface transmit delay, router priority, router dead and hello intervals, and authentication key.
•
Virtual links are supported.
•
Not-so-stubby-areas (NSSAs) per RFC 1587are supported.
OSPF typically requires coordination among many internal routers, area border routers (ABRs)
connected to multiple areas, and autonomous system boundary routers (ASBRs). The minimum
configuration would use all default parameter values, no authentication, and interfaces assigned to areas.
If you customize your environment, you must ensure coordinated configuration of all routers.
