The isis timer hello command sets the interval for sending Hello packets on an IS-IS interface.
The undo isis timer hello command restores the default setting.
By default, the interval for sending Hello packets 10 seconds on an interface.
isis timer hello hello-interval [ level-1 | level-2 ] [ conservative ]
undo isis timer hello [ hello-interval ] [ level-1 | level-2 ] [ conservative ]
| Parameter | Description | Value |
|---|---|---|
| hello-interval | Specifies the interval for sending Hello packets. | The value is an integer that ranges from 3 to 255, in seconds. The default value is 10 seconds. |
| level-1 | Indicates the interval for sending Level-1 Hello packets. If the level is not specified, the interval for sending Level-1 and Level-2 Hello packets is set by default. |
- |
| level-2 | Indicates the interval for sending Level-2 Hello packets. If the level is not specified, the interval for sending Level-1 and Level-2 Hello packets is set by default. NOTE:
Parameters level-1 and level-2 are configured only on a broadcast interface that is enabled with IS-IS. Level-1 and Level-2 Hello packets are sent separately and their intervals must be set respectively. There is only one Hello packet on a point-to-point link. Therefore, level-1 and level-2 parameters are not used. |
- |
| conservative | Indicates the conservative mode of the dead timer. If the conservative mode is configured, the value configured for the dead timer takes effect even when the value is less than 10s. | - |
IS-IS maintains neighbor relationships between neighbors by sending and receiving Hello packets. If the local device does not receive Hello packets from its neighbor within a specified period, the device considers the neighbor Down.
Prerequisites
IS-IS has been enabled on the interface using the isis enable command.
PrecautionsThe shorter the interval, the more system resources used to send Hello packets. The interval should therefore be set according to the actual conditions.
If a broadcast interface is emulated as a P2P interface through the isis circuit-type command or then restored to the broadcast interface through the undo isis circuit-type command, the interval for sending IS-IS Hello packets is restored to the default value.
# Set the interval for sending Level-2 Hello packets to 20 seconds on VLANIF100.
<HUAWEI> system-view [HUAWEI] isis [HUAWEI-isis-1] network-entity 01.0000.0000.0001.00 [HUAWEI-isis-1] quit [HUAWEI] interface vlanif 100 [HUAWEI-Vlanif100] isis enable 1 [HUAWEI-Vlanif100] isis timer hello 20 level-2
# Set the interval for sending Level-2 Hello packets to 20 seconds on GE0/0/1.
<HUAWEI> system-view [HUAWEI] isis [HUAWEI-isis-1] network-entity 01.0000.0000.0001.00 [HUAWEI-isis-1] quit [HUAWEI] interface gigabitethernet 0/0/1 [HUAWEI-GigabitEthernet0/0/1] undo portswitch [HUAWEI-GigabitEthernet0/0/1] isis enable 1 [HUAWEI-GigabitEthernet0/0/1] isis timer hello 20 level-2