VPLS MAC Ping
VPLS MAC ping is used to check whether a VPLS network path is reachable. It can check whether a VPLS path to the destination MAC address exists on the VPLS network and whether a specified MAC address exists on the destination end.
- Currently, VPLS MAC ping is supported in common VPLS, HVPLS, BGP AD VPLS, and BD accessing VPLS scenarios.
- VPLS MAC ping is supported in active-active scenarios.
In Figure 1, CE1 and CE2 are user access devices directly connected to the network.
The process of initiating a VPLS MAC ping test from PE1 is as follows:
The VSI and MAC address must be specified. The MAC address can be the bridge MAC address of the peer PE (PE2) on the VPLS network or the MAC address on the user CE side (CE2). A UDP MPLS Echo Request packet is constructed, and an IP address on the network segment 127.0.0.0/8 is used as the destination IP address in the IP header. The packet is then forwarded based on the MAC address entries.
- If a MAC address entry learned from the PW side is matched, the packet is forwarded only to the PW.
- If no MAC address entry is matched, the packet is broadcasted to all PWs corresponding to the VSI.
- PE2 listens to port 3503 for the MPLS Echo Request packet and returns an MPLS Echo Reply packet as a response.
- If the MAC address specified by the request end is the MAC address of CE2, the request packet is not forwarded to CE2. Instead, PE2 to which CE2 is connected checks whether this MAC address exists. If the MAC address exists, the request packet is sent successfully; if the MAC address does not exist, the request packet fails to be sent. In this manner, the test result is obtained. PE1 then calculates the communication time between PE1 and PE2 based on the time difference between when PE1 sends the MPLS Echo Request packet and when PE1 receives the MPLS Echo Reply packet. Such information clearly reflects the VPLS network performance.