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Cisco ME 3800X and 3600X Switch Software Configuration Guide
OL-23400-01
Chapter 29 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 feature 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 LSAs the router is refreshing,
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 database (40 to 100 LSAs),
increasing the pacing interval to 10 to 20 minutes might benefit you slightly.
Step 3
summary-address address mask
(Optional) Specify an address and IP subnet mask for redistributed
routes so that only one summary route is advertised.
Step 4
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 page 29-25
for parameter
definitions and
Table 29-5 on page 29-23
for virtual link defaults.
Step 5
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.
Step 6
ip ospf name-lookup
(Optional) Configure DNS name lookup. The default is disabled.
Step 7
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.
Step 8
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.
Step 9
passive-interface type number
(Optional) Suppress the sending of hello packets through the
specified interface.
Step 10
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.
Step 11
ospf log-adj-changes
(Optional) Send syslog message when a neighbor state changes.
Step 12
end
Return to privileged EXEC mode.
Step 13
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 29-33
.
Step 14
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Command
Purpose