stp vpls-subinterface enable
Function
The stp vpls-subinterface enable command enables a main interface to notify its sub-interface bound to a VSI of the received TC BPDUs.
The undo stp vpls-subinterface enable command disables a main interface from notifying its sub-interface bound to a VSI of the received TC BPDUs.
By default, a main interface is disabled from notifying its sub-interface bound to a VSI of the received TC BPDUs.
Only the S5720-EI, S5720-HI, S5730-HI, S5731-H, S5731S-H, S5732-H, S6720-EI, S6720-HI, S6720S-EI, S6730S-H, and S6730-H support this command.
Views
GE interface view, XGE interface view, 25GE interface view, 40GE interface view, 100GE interface view, Eth-Trunk interface view, port group view
Usage Guidelines
Usage Scenario
If an MSTP-enabled interface has a sub-interface configured with L2VPN, you can run the stp vpls-subinterface enable command to enable the main interface to notify its sub-interface bound to a VSI of the received TC BPDUs. After the main interface receives TC BPDUs, the main interface can notify the sub-interface bound to the VSI of updating MAC address entries and ARP entries. This function ensures nonstop services. When the stp vpls-subinterface enable command is used and the main interface is in Discarding state, the sub-interface bound to the VSI enters the flowdown state. This prevents loops on a VPLS network when CEs are dual-homed to PEs.
This command does not take effect when VBST is running. If this command has been run in STP/RSTP/MSTP mode, switching the STP/RSTP/MSTP mode to VBST mode fails, and the system displays a message indicating switching failure
Precautions
When the forwarding status of an interface moves to Discarding, its VSI-bound sub-interfaces will move to the Discarding state to prevent loops on the VPLS network on which a CE is dual-homed to two PEs.
The stp vpls-subinterface enable and erps vpls-subinterface enable commands are mutually exclusive on the same interface.