3Com Switch 4800G 24-Port - Page 301

Configuring OSPF Network Optimization 301
■ Change 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. It 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 retransmission timer: Interval within which if the interface receives no
acknowledgement packets after sending a LSA to the neighbor, it will
retransmit the LSA.
Follow these steps to configure timers for OSPF packets:
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 default dead interval is 40
seconds on P2P, Broadcast interfaces
and 120 seconds on P2MP and
NBMA interfaces.
Specify the
retransmission interval
ospf timer retransmit
interval
Optional
The retransmission interval defaults
to 5 seconds.