Cisco Systems 78-11741-02 Wireless Office Headset User Manual


 
Configuring OSPF
Logging Neighbors Going Up or Down
IPC-235
Cisco IOS IP Configuration Guide
Implementation Considerations
Evaluate the following considerations before implementing this feature:
Because LSAs that include topology changes are flooded over an on-demand circuit, we recommend
that you put demand circuits within OSPF stub areas or within NSSAs to isolate the demand circuits
from as many topology changes as possible.
To take advantage of the on-demand circuit functionality within a stub area or NSSA, every router
in the area must have this feature loaded. If this feature is deployed within a regular area, all other
regular areas must also support this feature before the demand circuit functionality can take effect
because type 5 external LSAs are flooded throughout all areas.
Hub-and-spoke network topologies that have a point-to-multipoint (p2mp) OSPF interface type on
a hub might not revert back to non-demand circuit mode when needed. You must simultaneously
reconfigure OSPF on all interfaces on the p2mp segment when reverting them from demand circuit
mode to non-demand circuit mode.
Do not implement this feature on a broadcast-based network topology because the overhead
protocols (such as hello and LSA packets) cannot be successfully suppressed, which means the link
will remain up.
Configuring the router for an OSPF on-demand circuit with an asynchronous interface is not a
supported configuration. The supported configuration is to use dialer interfaces on both ends of the
circuit. For more information, refer to the following TAC URL:
http://www.cisco.com/warp/public/104/dcprob.html#reason5
Logging Neighbors Going Up or Down
By default, the system sends a syslog message when an OSPF neighbor goes up or down. If you turned
off this feature and want to restore it, use the following command in router configuration mode:
Configure this command if you want to know about OSPF neighbors going up or down without turning
on the debug ip ospf adjacency EXEC command. The log-adjacency-changes router configuration
command provides a higher level view of the peer relationship with less output. Configure
log-adjacency-changes detail if you want to see messages for each state change.
Changing the LSA Group Pacing
The OSPF LSA group pacing feature allows the router to group OSPF LSAs and pace the refreshing,
checksumming, and aging functions. The group pacing results in more efficient use of the router.
The router groups OSPF LSAs and paces the refreshing, checksumming, and aging functions so that
sudden increases in CPU usage and network resources are avoided. This feature is most beneficial to
large OSPF networks.
Command Purpose
Router(config-router)# log-adjacency-changes
[detail]
Sends syslog message when an OSPF neighbor goes up or down.