Building a Virtual Layer 2 Network Using Ethernet over GRE
In Figure 1, SwitchA connects to a branch Ethernet and SwitchB connects to a headquarters Ethernet. The headquarters and branch communicate over the IP/MPLS backbone network. The customer wants to transparently transmit Ethernet packets over a GRE tunnel, implementing Layer 2 communication between the headquarters and branch.
To implement Layer 2 communication between the headquarters and branch, you can configure Ethernet over GRE on SwitchA and SwitchB. Create VE interfaces on SwitchA and SwitchB, add them to a VLAN, and bind them to a GRE tunnel. The VE interface sends Ethernet packets from the specified VLAN to the GRE tunnel, implementing Layer 2 communication between the headquarters and branch.