When a device withdraws MAC routes, the MAC maintenance function is enabled by default. That is, the device does not process the received MAC route withdrawal message and retains the original MAC route for a period of time. This function is used to prevent MAC route flapping in a fault recovery switchback scenario. In the following scenarios, you need to run this command on a remote PE to disable MAC address maintenance:
Traditional VPLS and EVPN VPLS
Dual-homing to EVPN through Eth-Trunk interfaces (LACP deployed)
When a CE is dual-homed to PEs, there is no upstream traffic from the CE to the PEs.
In the preceding scenario, when services are switched back after the fault is rectified, the device on the backup path clears MAC addresses. In this case, the remote PE maintains MAC addresses by default. As a result, traffic is still diverted to the device on the backup path, causing traffic loss.