L2 Broadcast Storms and MAC Address Table Thrashing

This video shows what causes Data Link Layer 2 Ethernet broadcast storms and MAC address table thrashing that you can avoid using the Spanning Tree Protocol and EtherChannel protocols.

Layer 2 Data Link (also known as Ethernet) frames do not expire. An Ethernet frame sent to an unknown MAC address could bounce forever in the network. This is not good since it wastes bandwidth and compute resources. This problem is exacerbated when several switches are interconnected together with redundant links. It is best practice to use redundant links to inter-connect Layer 2 switches to mitigate inter-switch link failure risks. However, this amplifies the risk to have frames bouncing back and forth between switches.