3Com Switch 8800 Advanced Software V5 Configuration Guide

Configuring OSPF Network Optimization 331
■ Change values of OSPF packet timers to adjust the OSPF network convergence
speed and network load. On low speed links, you need to consider the delay
time for sending LSAs on interfaces.
■ Change the interval for SPF calculation to reduce resource consumption caused
by frequent network changes.
■ Configure OSPF authentication to meet high security requirements of some
mission-critical networks.
■ Configure OSPF network management functions, such as binding OSPF MIB
with a process, sending trap information and collecting log information.
Prerequisites Before configuring OSPF network optimization, you have configured:
■ IP addresses for interfaces
■ OSPF basic functions
Configuring OSPF Packet
Timers
You can configure the following timers on OSPF interfaces as needed:
■ Hello timer: Interval for sending hello packets, must be identical on OSPF
neighbors. The longer the interval, the lower convergence speed and smaller
network load.
■ Poll timer: Interval for sending hello packets to the neighbor that is down on
the NBMA network.
■ Dead timer: Interval within which if the interface receives no hello packet from
the neighbor, it declares the neighbor is down.
■ LSA retransmit timer: Interval within which if the interface receives no
acknowledgement packets after sending a LSA to the neighbor, it will
retransmit the LSA.
To configure timers for OSPF packets, use the following commands:
To do... Use the command... Remarks
Enter system view system-view -
Enter interface view interface interface-type
interface-number
-
Specify the hello interval ospf timer hello seconds Optional
The hello interval on P2P,
Broadcast interfaces defaults to
10 seconds and defaults to 30
seconds on P2MP and NBMA
interfaces.
Specify the poll interval ospf timer poll seconds Optional
The poll interval defaults to
120 seconds.
Specify the dead interval ospf timer dead seconds Optional
The dead interval defaults to
40 seconds on P2P, Broadcast
interfaces and 120 seconds on
P2MP and NBMA interfaces.