(Optional) Configuring the Active/Standby Link Switchover Mode

Context

In N+1 backup scenarios, APs set up links only with the primary ACs. When a link between an AP and a primary AC fails, the AP sets up a link with the backup AC and goes online on the backup AC. When the primary AC is recovered, a revertive switchover is triggered. The AP switches the link back to the primary AC after 20 echo intervals.

To enable an AP to preferentially switch service traffic to the active link, set the active/standby link switchover mode to the priority mode.
To allow an AP to use a link with high network stabilization, set the active/standby link switchover mode to the network stabilization mode. When the condition for triggering an active/standby link switchover is met, the AP preferentially switches service traffic to the link on a network with higher network stabilization. In this case, whether an active/standby link switchover is performed is only related to the network stabilization of links but not related to the active and standby roles of links. You can run the ac protect link-switch packet-loss { gap-threshold gap-threshold | start-threshold start-threshold } command to configure the condition for triggering an active/standby link switchover.

In N+1 backup scenarios, the network stabilization of the link between an AP and the current AC is determined by the Echo packet loss rate, and that of the link between the AP and another AC is determined by the Primary Discovery packet loss rate. The active/standby link switchover is performed when the following conditions are met:

APs collect statistics about Echo or Primary Discovery packets and find that the calculated packet loss rate is higher than the packet loss rate start threshold.
The packet loss rate of the link in use is higher than that of the other link, and the difference between the two links' packet loss rates is higher than the packet loss rate difference threshold.

Procedure

Run system-view
The system view is displayed.
Run wlan
The WLAN view is displayed.
Run ap-system-profile name profile-name
An AP system profile is created and the AP system profile view is displayed.

By default, the system provides the AP system profile default.
Run ac protect link-switch mode { priority | network-stabilization }
The active/standby link switchover mode is configured.

By default, the active/standby link switchover mode is the priority mode.
Run ac protect link-switch packet-loss echo-probe-time echo-probe-time
The number of Echo probe packets sent within a statistics collection interval is configured.

By default, the number of Echo packets sent within a statistics collection interval is 20.

This configuration is supported only when the active/standby link switchover mode is set to the network stabilization mode using the ac protect link-switch mode network-stabilization command.
Run ac protect link-switch packet-loss { gap-threshold gap-threshold | start-threshold start-threshold }
The packet loss rate start and difference thresholds for an active/standby link switchover are configured.

By default, the packet loss rate start and difference thresholds for an active/standby link switchover are 20% and 15%, respectively.

This configuration is supported only when the active/standby link switchover mode is set to the network stabilization mode using the ac protect link-switch mode network-stabilization command.
Run quit
Return to the WLAN view.
Bind the AP system profile to the AP group.
- Binding an AP system profile to an AP group.
  1. Run the ap-group name group-name command to enter the AP group view.
  2. Run the ap-system-profile profile-name command to bind the AP system profile to the AP group.
    
    By default, the AP system profile default is bound to an AP group.
- Binding an AP system profile to an AP.
  1. Run the ap-id ap-id, ap-mac ap-mac, or ap-name ap-name command to enter the AP view.
  2. Run the ap-system-profile profile-name command to bind the AP system profile to the AP.
    
    By default, no AP system profile is bound to an AP.

Verifying the Configuration

Run the display ap-system-profile { all | name profile-name } command to check the configurations related to the active/standby link switchover mode.