Concept Guide

To congure a stub area, use the following commands.
1 Review all areas after they were congured to determine which areas are NOT receiving type 5 LSAs.
EXEC Privilege mode
show ip ospf process-id [vrf] database database-summary
2 Enter CONFIGURATION mode.
EXEC Privilege mode
configure
3 Enter ROUTER OSPF mode.
CONFIGURATION mode
router ospf process-id [vrf]
Process ID is the ID assigned when conguring OSPFv2 globally.
4 Congure the area as a stub area.
CONFIG-ROUTER-OSPF-id mode
area area-id stub [no-summary]
Use the keywords no-summary to prevent transmission into the area of summary ASBR LSAs.
Area ID is the number or IP address assigned when creating the area.
Example of the show ip ospf database database-summary Command
To view which LSAs are transmitted, use the show ip ospf database process-id database-summary command in EXEC
Privilege mode.
Dell#show ip ospf 34 database database-summary
OSPF Router with ID (10.1.2.100) (Process ID 34)
Area ID Router Network S-Net S-ASBR Type-7 Subtotal
2.2.2.2 1 0 0 0 0 1
3.3.3.3 1 0 0 0 0 1
Dell#
To view information on areas, use the show ip ospf process-id command in EXEC Privilege mode.
Conguring LSA Throttling Timers
Congured link-state advertisement (LSA) timers replace the standard transmit and acceptance times for LSAs.
The LSA throttling timers are congured in milliseconds. The interval time increases exponentially until a maximum time is reached. If the
maximum time is reached, the system continues to transmit at the maximum interval. If the system is stable for twice the maximum interval
time, it reverts to the start-interval timer. The cycle repeats.
To congure the LSA throttling timers, use the following commands.
1 Specify the interval times for all LSA transmissions. CONFIG-ROUTER-OSPF-id mode. timers throttle lsa all {start-
interval | hold-interval | max-interval} To set the minimum interval between initial sending and resending the same LSA,
use the keywords start-interval. To set the next interval to send the same LSA, use the keywords hold-interval. The
hold-interval is the time between sending the same LSA after the start-interval is attempted. To set the maximum amount of time the
system waits before sending the LSA, use the keywords
max-interval. The interval range is 0 to 600,000 milliseconds.
2 Specify the interval for LSA acceptance. CONFIG-ROUTER-OSPF-id mode. timers throttle lsa all arrival-time
696
Open Shortest Path First (OSPFv2 and OSPFv3)