MCLAG makes two switches look like one to a third device, so CE can bundle one link to each of them with ordinary LACP, and both links forward. CE is ready. Build the pair on L1 and L2, then the port-channel to CE.
The simulator ticks each one as soon as the network meets it.
On L1 and L2, create VLAN 10 and the control VLAN 4000: 172.16.0.1/30 on L1, 172.16.0.2/30 on L2.
Build PortChannel 100 carrying VLANs 10 and 4000, with Eth1/5 and Eth1/6 as members. Then mclag domain 1: source-ip, peer-ip, peer-link PortChannel100 and the same mclag-system-mac on both.
On both, build PortChannel 1 in VLAN 10 with mclag 1, and add Eth1/3.
CE bundles both its links: show mclag brief shows PortChannel1 up on both switches.
On L2, put Eth1/7 in VLAN 10, then ping PC2 from PC1.
