OSPF - Update pacing timers
Where OSPF LSA throttling timers adjust the delay of the generation of LSAs during network instability, the pacing timers are used to adjust the rate at which OSPF LSA flood pacing, retransmission pacing, and group pacing updates occur. You can see these options in the following CLI context sensitive help:
R1(config-router)#timers pacing ? flood OSPF flood pacing timer lsa-group OSPF LSA group pacing timer retransmission OSPF retransmission pacing timer R1(config-router)#timers pacing
- Flood pacing - Configuring OSPF flood pacing timers allows you to control interpacket spacing between consecutive link-state update packets in the OSPF transmission queue. (Default 33 milliseconds)
- Retransmission pacing - Configuring OSPF retransmission pacing timers allows you to control interpacket spacing between consecutive link-state update packets in the OSPF retransmission queue. (Default 240 seconds)
- Group pacing - Cisco IOS software groups the periodic refresh of LSAs to improve the LSA packing density for the refreshes in large topologies. The group timer controls the interval used for group LSA refreshment; however, this timer does not change the frequency that individual LSAs are refreshed which is every 30 minutes. (Default 66 milliseconds)
The default settings for OSPF packet pacing timers are suitable for the majority of OSPF deployments. You should change the default timers only as a last resort.
Links:
https://forum.networklessons.com/t/ospf-lsa-throttling/1962/23?u=lagapidis