Configuring EVPN in Ring Network Access Mode
If EVPN VPLS over MPLS or EVPN VPLS over SRv6 in ring network access mode needs to be deployed on a network, you need to configure EVPN in this mode and deploy a loop avoidance protocol to prevent loops.
Context
On the network shown in Figure 1, EVPN VPLS over MPLS or EVPN VPLS over SRv6 needs to be deployed between PEs, and a loop avoidance protocol (MSTP in this example) needs to be deployed on the ring network formed by PE1, PE2, CE1, and CE2. Currently, STP, ERPS, and MSTP can be deployed.
Pre-configuration Tasks
Before configuring EVPN VPLS in ring network access mode, complete the following tasks:
- Configure EVPN VPLS over SRv6 BE, EVPN VPLS over SRv6 TE Policy, or EVPN VPLS over MPLS on PEs.
- Configure BD EVPN functions on PEs.
- Configure basic IPv4 IS-IS functions on PEs and CEs.
- Configure a loop avoidance protocol on PEs and CEs. For details, see MSTP Configuration, STP and RSTP Configuration, or ERPS (G.8032) Configuration.
- Configuring Ring Network Topology Isolation
- In scenarios where multiple ring networks that belong to the same BD but different VLANs connect to an EVPN, you can configure ring network topology isolation on AC sub-interfaces. This configuration isolates the topologies of these ring networks and reduces the number of Layer 2 protocol packets transparently transmitted between the networks. In this way, the sub-interfaces transparently transmit Layer 2 protocol packets only after the packets pass the VLAN check on these sub-interfaces.
- Configuring Ring Network Access
- If MSTP is deployed on a ring network, run the evpn stp-ring-id command on dual-homing PEs to configure the same ring ID for them. The dual-homing PEs are then identified by the same ring ID.
- Verifying the Configuration
- After EVPN in ring network access mode is configured, you can view the spanning tree status of ports in the MSTP process on ring network devices and view EVPN routing information on PEs.