R3166-R3206-HP High-End Firewalls Network Management Configuration Guide-6PW101

293
• 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 retransmits 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.
NOTE:
• The hello and dead intervals restore to default values after you chan
g
e the network type for an interface.
• The dead interval should be at least four times the hello interval on an interface.
• The poll interval is at least four times the hello interval.
• The retransmission interval should not be so small to avoid unnecessary LSA retransmissions. In
g
eneral,
this value is bigger than the round-trip time of a packet between two neighbors.
Specifying an LSA transmission delay
OSPF packets need time for traveling on links, so it is necessary to add a transmission delay into the age
time, especially for low speed links.
Follow these steps to specify an LSA transmission delay on an interface:
To do… Use the command…
Remarks
Enter system view system-view
—