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Cisco ME 3400 EthernetAccess Switch SoftwareConfiguration Guide
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Chapter32 Configuring IP Unicast Routing
Configuring OSPF
Changing LSA Group Pacing
The OSPF LSA group pacing feature allows the router to group OSPF LSAs and pace the refreshing,
check-summing, and aging functions for more efficient router use. This featu re is enabled by default with
a 4-minute default pacing interval, and you will not usually need to modify this parameter. The optimum
group pacing interval is inversely proportional to the number of LSA s t h e rou t er i s r e freshi ng ,
check-summing, and aging. For example, if you have approximately 10,000 LSAs in the database,
decreasing the pacing interval would benefit you. If you have a very small databa se ( 40 to 1 00 LSAs),
increasing the pacing interval to 10 to 20 minutes might benefit you slightly.
Beginning in privileged EXEC mode, follow these steps to configure OSPF LSA pacing:
Step4 area area-id virtual-link router-id
[hello-interval seconds]
[retransmit-interval seconds] [trans]
[[authentication-key key] |
message-digest-key keyid md5 key]]
(Optional) Establish a virtual link and set its parameters. See the
“Configuring OSPF Interfaces” section on page32-26 for parameter
definitions and Table32-5 on pa ge 32-24 for virtual link defaults.
Step5 default-information originate [always]
[metric metric-value] [metric-type
type-value] [route-map map-name]
(Optional) Force the ASBR to generate a default route into the OSPF
routing domain. Parameters are all optional.
Step6 ip ospf name-lookup (Optional) Configure DNS name lookup. The default is disabled.
Step7 ip auto-cost reference-bandwidth ref-bw (Optional) Specify an address range for which a single route will be
advertised. Use this command only with area border routers.
Step8 distance ospf {[inter-area dist1] [inter-area
dist2] [external dist3]} (Optional) Change the OSPF distance values. The default distance
for each type of route is 110. The range is 1 to 255.
Step9 passive-interface type number (Optional) Suppress the sending of hello packets through the
specified interface.
Step10 timers throttle spf spf-delay spf-holdtime
spf-wait (Optional) Configure route calculation timers.
•spf-delay—Delay between receiving a change to SPF
calculation. The range is from 1 to 600000. miliseconds.
•spf-holdtime—Delay between first and second SPF calculation.
The range is form 1 to 600000 in milliseconds.
•spf-wait—Maximum wait time in milliseconds for SPF
calculations. The range is from 1 to 600000 in milliseconds.
Step11 ospf log-adj-changes (Optional) Send syslog message when a neighbor state ch an ges.
Step12 end Return to privileged EXEC mode.
Step13 show ip ospf [process-id [area-id]] database Display lists of information related to the OSPF database for a
specific router. For some of the keyword options, see the “Monitoring
OSPF” section on page 32-31.
Step14 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 router ospf process-id Enable OSPF routing, and enter router configuration mode.