Cisco Systems OL-4580-01 Setting the Priority of the CSS, Setting the Retransmission Interval

Chapter 3 Configuring Open Shortest Path First (OSPF)

Configuring OSPF on a CSS IP Interface

For example, to set the poll interval to 200 seconds, enter:

(config-circuit-ip[VLAN6-3.1.2.2])# ospf poll 200

To reset the poll interval to the default value of 120 seconds, enter:

(config-circuit-ip[VLAN6-3.1.2.2])# no ospf poll

Setting the Priority of the CSS

To avoid the need for each router on a LAN to talk to every router on a network that has more than two attached routers, one router is elected as the designated router. Designated routers advertise network link states for attached network segments. An LSA lists all routers that are connected to a segment.

The priority determines which router is the designated router. The router with the highest priority becomes the designated router. In case of a tie, routers use their router ID as a tie breaker.

Use the ospf priority command to set the router priority for the interface. The priority of the interface is an integer from 0 to 255. The default is 1, which is the highest router priority. A value of 0 signifies that the CSS is not eligible to become the designated router on a particular network.

If a designated router exists on the network, it remains the designated router regardless of its router priority.

To make the interface ineligible to become a designated router, enter:

(config-circuit-ip[VLAN6-3.1.2.2])# ospf priority 0

To reset the router priority to the default value of 1, enter:

(config-circuit-ip[VLAN6-3.1.2.2])# no ospf priority

Setting the Retransmission Interval

The retransmission interval is the number of seconds between link-state advertisement retransmissions for adjacencies belonging to an interface. OSPF creates adjacencies between neighboring routers for the purpose of exchanging routing information. The CSS also uses the interval when retransmitting database descriptions and link-state request packets.

Use the ospf retransmit command to set the retransmit interval for the interface. Enter a number from 1 to 3600 seconds (1 hour). The default is 5 seconds.

	Cisco Content Services Switch Routing and Bridging Configuration Guide
OL-4580-01		3-27