The multicast-domain switch-delay command specifies the delay for the switchover from the Share-MDT to Switch-MDT in a specified VPN instance.
The undo multicast-domain switch-delay command restores the default value of the delay.
By default, the delay for the switchover from the Share-MDT to Switch-MDT is 5 seconds.
| Parameter | Description | Value |
|---|---|---|
| switch-delay | Specifies the delay for the switchover from the Share-MDT to Switch-MDT. | The value of the delay is an integer that ranges from 3 to 60, in seconds. |
Usage Scenario
In some cases, the forwarding rate of VPN multicast data packets fluctuates above and below the switchover threshold. To prevent frequent switchovers between the Share-MDT and Switch-MDT, configure a delay for the switchover from the Share-MDT to Switch-MDT. When detecting that the forwarding rate is higher than the switchover threshold, the system does not immediately perform the switchover but starts the Switch-Delay timer. Before the Switch-Delay timer expires, the system continues to detect the data forwarding rate. If the rate remains higher than the switchover threshold throughout the duration of the Switch-Delay timer, the transmission path of data packets is switched to the Switch-MDT; otherwise, the packets are still forwarded along the Share-MDT.
Prerequisites
The Share-Group has been configured using the multicast-domain share-group binding command in the VPN instance.
Precautions
During a switchover, there is a delay about 1 to 30 seconds from the time when the forwarding rate ranges to the time when the system starts the Switch-Delay timer. The delay is not included in the value of the Switch-Delay. Consequently, the total delay from the time when the forwarding rate of the data changes to the time when the system completes the switchover is 1-30 seconds longer than the Switch-Delay.
# Specify the delay for the switching to Switch-MDT to 20 seconds in VPN instance mytest.
<HUAWEI> system-view [HUAWEI] ip vpn-instance mytest [HUAWEI-vpn-instance-mytest] route-distinguisher 11:11 [HUAWEI-vpn-instance-mytest-af-ipv4] multicast routing-enable [HUAWEI-vpn-instance-mytest-af-ipv4] multicast-domain share-group 224.1.1.1 binding mtunnel 0 [HUAWEI-vpn-instance-mytest-af-ipv4] multicast-domain switch-delay 20