Cisco Systems 78-11741-02 manual Displaying Ospf Update Packet Pacing, IPC-239

Configuring OSPF

Displaying OSPF Update Packet Pacing

Displaying OSPF Update Packet Pacing

The former OSPF implementation for sending update packets needed to be more efficient. Some update packets were getting lost in cases where the link was slow, a neighbor could not receive the updates quickly enough, or the router was out of buffer space. For example, packets might be dropped if either of the following topologies existed:

•A fast router was connected to a slower router over a point-to-point link.

•During flooding, several neighbors sent updates to a single router at the same time.

OSPF update packets are now automatically paced so they are not sent less than 33 milliseconds apart. Pacing is also added between resends to increase efficiency and minimize lost retransmissions. Also, you can display the LSAs waiting to be sent out an interface. The benefit of the pacing is that OSPF update and retransmission packets are sent more efficiently.

There are no configuration tasks for this feature; it occurs automatically.

To observe OSPF packet pacing by displaying a list of LSAs waiting to be flooded over a specified interface, use the following command in EXEC mode:

Command	Purpose
Router# show ip ospf flood-list	Displays a list of LSAs waiting to be flooded over an interface.
interface-type interface-number

Cisco IOS IP Configuration Guide

IPC-239