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Cisco ME 3800X and 3600X Switch Software Configuration Guide
OL-23400-01
Chapter 29 Configuring IP Unicast Routing
Configuring OSPF
Configuring OSPF Network Types
OSPF classifies different media into the three types of networks by default:
•
Broadcast networks (Ethernet, Token Ring, and FDDI)
•
Nonbroadcast multiaccess (NBMA) networks (Switched Multimegabit Data Service [SMDS],
Frame Relay, and X.25)
•
Point-to-point networks (High-Level Data Link Control [HDLC], PPP)
You can also configure network interfaces as either a broadcast or an NBMA network and as point-to
point or point-to-multipoint, regardless of the default media type.
Configuring OSPF for Nonbroadcast Networks
Because many routers might be attached to an OSPF network, a designated router is selected for the
network. If broadcast capability is not configured in the network, the designated router selection requires
special configuration parameters. You need to configure these parameters only for devices that are
eligible to become the designated router or backup designated router (in other words, routers with a
nonzero router priority value).
Beginning in privileged EXEC mode, follow these steps to configure routers that interconnect to
nonbroadcast networks:
On point-to-multipoint, nonbroadcast networks, you then use the neighbor router configuration
command to identify neighbors. Assigning a cost to a neighbor is optional.
Configuring Network Types for OSPF Interfaces
You can configure network interfaces as either broadcast or NBMA and as point-to point or
point-to-multipoint, regardless of the default media type.
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
router ospf process-id
Configure an OSPF routing process and enter router configuration
mode.
Step 3
neighbor ip-address [priority number]
[poll-interval seconds]
Specify an OSPF neighbor with neighbor parameters as required.
•
ip-address—Enter the interface IP address of the OSPF
neighbor.
•
(Optional) priority number—Specify the router priority value
of the nonbroadcast neighbor associated with the IP address. The
range is 0 to 255; the default is 0.
•
(Optional) poll-interval seconds—Specify a number that
represents the poll interval time (in seconds). This value should
be much larger than the hello interval. The range is
0-4294967295; the default is 120 seconds (2 minutes).
Step 4
end
Return to privileged EXEC mode.
Step 5
show ip ospf [process-id]
Display OSPF-related information.
Step 6
copy running-config startup-config
(Optional) Save your entries in the configuration file.
