OSPFv3 Fast Convergence: LSA and SPF Throttling
The Open Shortest Path First version 3 (OSPFv3) link-state advertisement (LSAs) and shortest-path first (SPF) throttling feature provides a dynamic mechanism to slow down link-state advertisement updates in OSPFv3 during times of network instability. It also allows faster OSPFv3 convergence by providing LSA rate limiting in milliseconds.
Information About OSPFv3 Fast Convergence: LSA and SPF Throttling
Fast Convergence: LSA and SPF Throttling
The OSPFv3 LSA and SPF throttling feature provides a dynamic mechanism to slow down link-state advertisement updates in OSPFv3 during times of network instability. It also allows faster OSPFv3 convergence by providing LSA rate limiting in milliseconds.
OSPFv3 can use static timers for rate-limiting SPF calculation and LSA generation. Although these timers are configurable, the values used are specified in seconds, which poses a limitation on OSPFv3 convergence. LSA and SPF throttling achieves subsecond convergence by providing a more sophisticated SPF and LSA rate-limiting mechanism that is able to react quickly to changes and also provide stability and protection during prolonged periods of instability.
How to Configure OSPFv3 Fast Convergence: LSA and SPF Throttling
Tuning LSA and SPF Timers for OSPFv3 Fast Convergence
SUMMARY STEPS
- enable
- configure terminal
- router ospfv3 [process-id ]
- timers lsa arrival milliseconds
- timers pacing flood milliseconds
- timers pacing lsa-group seconds
- timers pacing retransmission milliseconds
DETAILED STEPS
Command or Action | Purpose | |
---|---|---|
Step 1 |
enable Example:
|
Enables privileged EXEC mode.
|
Step 2 |
configure terminal Example:
|
Enters global configuration mode. |
Step 3 |
router ospfv3 [process-id ] Example:
|
Enables OSPFv3 router configuration mode for the IPv4 or IPv6 address family. |
Step 4 |
timers lsa arrival milliseconds Example:
|
Sets the minimum interval at which the software accepts the same LSA from OSPFv3 neighbors. |
Step 5 |
timers pacing flood milliseconds Example:
|
Configures LSA flood packet pacing. |
Step 6 |
timers pacing lsa-group seconds Example:
|
Changes the interval at which OSPFv3 LSAs are collected into a group and refreshed, checksummed, or aged. |
Step 7 |
timers pacing retransmission milliseconds Example:
|
Configures LSA retransmission packet pacing in IPv4 OSPFv3. |
Configuring LSA and SPF Throttling for OSPFv3 Fast Convergence
SUMMARY STEPS
- enable
- configure terminal
- ipv6 router ospf process-id
- timers throttle spf spf-start spf-hold spf-max-wait
- timers throttle lsa start-interval hold-interval max-interval
- timers lsa arrival milliseconds
- timers pacing flood milliseconds
DETAILED STEPS
Command or Action | Purpose | |
---|---|---|
Step 1 |
enable Example:
|
Enables privileged EXEC mode.
|
Step 2 |
configure terminal Example:
|
Enters global configuration mode. |
Step 3 |
ipv6 router ospf process-id Example:
|
Enables OSPFv3 router configuration mode. |
Step 4 |
timers throttle spf spf-start spf-hold spf-max-wait Example:
|
Turns on SPF throttling. |
Step 5 |
timers throttle lsa start-interval hold-interval max-interval Example:
|
Sets rate-limiting values for OSPFv3 LSA generation. |
Step 6 |
timers lsa arrival milliseconds Example:
|
Sets the minimum interval at which the software accepts the same LSA from OSPFv3 neighbors. |
Step 7 |
timers pacing flood milliseconds Example:
|
Configures LSA flood packet pacing. |
Configuration Examples for OSPFv3 Fast Convergence: LSA and SPF Throttling
Example: Configuring LSA and SPF Throttling for OSPFv3 Fast Convergence
The following example show how to display the configuration values for SPF and LSA throttling timers:
Device# show ipv6 ospf
Routing Process "ospfv3 1" with ID 10.9.4.1
Event-log enabled, Maximum number of events: 1000, Mode: cyclic
It is an autonomous system boundary router
Redistributing External Routes from,
ospf 2
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
Additional References
Related Documents
Related Topic |
Document Title |
---|---|
IPv6 addressing and connectivity |
IPv6 Configuration Guide |
OSPFv3 Fast Convergence: LSA and SPF Throttling |
OSPF Shortest Path First Throttling module |
Standards and RFCs
Standard/RFC |
Title |
---|---|
RFCs for IPv6 |
IPv6 RFCs |
Feature Information for OSPFv3 Fast Convergence: LSA and SPF Throttling
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Feature Name |
Releases |
Feature Information |
---|---|---|
OSPFv3 Fast Convergence: LSA and SPF Throttling |
Cisco IOS XE Fuji 16.8.1a |
The OSPFv3 LSA and SPF throttling feature provides a dynamic mechanism to slow down link-state advertisement updates in OSPFv3 during times of network instability. This feature was introduced. |