Stacking switches Part - III (Arista MLAG - Multi Chassis Link Aggregation)
Now it is time for the elephant in the room in the stacking series, which is called MLAG (multi chassis link aggregation). Vendors like Arista, Juniper, Extreme Networks, Cisco uses this as stacking method in their switches. Again this article is not a technical deep dive about MLAG, but rather looks at how it is configured in Arista switches. Let's define our network constraints; the example has following characteristics - Two Arista switches will run peering between them and will form MLAG. Two Cisco test switches will form multichassis link-aggregation with Arista switches. They will simulate the client connection. From test switches, we will test connectivity by using a vlan interface over the link-aggregated interfaces. Our network topology looks like this - Fig 01 - Arista MLAG Topology Two Arista switches SW-U01 and SW-U02 will use interface eth6 and eth7 for forming MLAG peering. Then they will run LACP based link-aggregation with Cisco test switch