Configuring the Interval for Sending Hello Packets
Context
Hello packets are periodically sent to the neighbor switch to detect and maintain the neighbor relationship and to elect the DR and the BDR. RFC 2328 requires that the Hello timer values of neighbors be consistent. The value of the Hello timer is inversely proportional to the route convergence speed and network load.
Do as follows on the switch that runs OSPFv3.
Procedure
- Run system-view
The system view is displayed.
- Run interface interface-type interface-number
The interface view is displayed.
- On an Ethernet interface, run undo portswitch
The interface is switched to Layer 3 mode.
By default, an Ethernet interface works in Layer 2 mode.
The mode switching function takes effect when the interface only has attribute configurations (for example, shutdown and description configurations). Alternatively, if configuration information supported by both Layer 2 and Layer 3 interfaces exists (for example, mode lacp and lacp system-id configurations), no configuration that is not supported after the working mode of the interface is switched can exist. If unsupported configurations exist on the interface, delete the configurations first and then run the undo portswitch command.
If many Ethernet interfaces need to be switched to Layer 3 mode, run the undo portswitch batch interface-type { interface-number1 [ to interface-number2 ] } &<1-10> command in the system view to switch these interfaces to Layer 3 mode in batches.
- Run ospfv3 timer hello interval [ conservative ] [ instance instance-id ]
The interval for sending Hello packets is set on the interface.
To speed up OSPFv3 convergence in the case of a link failure, Configuring BFD for OSPFv3 is recommended. If the remote end does not support BFD for OSPFv3 or you do not want to configure BFD for OSPFv3, specify conservative when you run the ospfv3 timer hello command. If the conservative mode is configured, the value configured for the dead timer using the ospfv3 timer dead command takes effect even when the value is less than 10s; if the value configured for the dead timer is greater than 10s, services may be affected.
The interval must be longer than or equal to the active/standby switchover period. Otherwise, a protocol intermittent interruption may occur during the switchover. The default interval for sending Hello packets is recommended. - Run commit
The configuration is committed.
