HP 6125XLG R2306-HP 6125XLG Blade Switch Layer 3 - IP Routing Configuration Gu - Page 79

Configuring OSPF timers An OSPF interface includes the following timers: • Hello timer-Interval for sending hello packets. It must be identical on OSPF neighbors. • Poll timer-Interval for sending hello packets to a 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. To configure OSPF timers: Step 1. Enter system view. 2. Enter interface view. Command system-view interface interface-type interface-number 3. Specify the hello interval. ospf timer hello seconds 4. Specify the poll interval. ospf timer poll seconds 5. Specify the dead interval. ospf timer dead seconds 6. Specify the retransmission interval. ospf timer retransmit interval Remarks N/A N/A By default: • The hello interval on P2P and broadcast interfaces is 10 seconds. • The hello interval on P2MP and NBMA interfaces is 30 seconds. The default hello interval is restored when the network type for an interface is changed. The default setting is 120 seconds. The poll interval is at least four times the hello interval. By default: • The dead interval on P2P and broadcast interfaces is 40 seconds. • The dead interval on P2MP and NBMA interfaces is 120 seconds. The dead interval must be at least four times the hello interval on an interface. The default dead interval is restored when the network type for an interface is changed. The default setting is 5 seconds. A retransmission interval setting that is too small can cause unnecessary LSA retransmissions. This interval is typically set bigger than the round-trip time of a packet between two neighbors. Specifying LSA transmission delay To avoid LSAs from aging out during transmission, set an LSA retransmission delay especially for low speed links. 68