H3C Technologies H3C WX6000 Series Access Controllers - Manual (Page 261)

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Prerequisites
Before configuring OSPF network optimization, you have configured:
z
IP addresses for interfaces;
z
OSPF basic functions.
Configuring OSPF Packet Timers
You can configure the following timers on OSPF interfaces as needed:
z
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.
z
Poll timer: Interval for sending hello packets to the neighbor that is down on the NBMA network.
z
Dead timer: Interval within which if the interface receives no hello packet from the neighbor, it
declares the neighbor is down.
z
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.
z
The hello and dead intervals restore to default values after you change the network type for an
interface.
z
The dead interval should be at least four times the hello interval on an interface.
z
The poll interval is at least four times the hello interval.
z
The retransmission interval should not be so small for avoidance of unnecessary LSA
retransmissions. In general, this value is bigger than the round-trip time of a packet between two
adjacencies.