Switching basics: Etherchannel Guard Misconfig Command

 Today I am going to talk about the Etherchannel  Guard and the case why we are using the Etherchannel Guard is the misconfiguration of the etherchannel in the network.

What is Etherchannel ?
Etherchannel port channel is the way to connect two different switches with two or more links and make them bundled in such a way that it looks like to be a single link.

Below is the demo topology showing the etherchannel between the switches with the terminology PAgP and LACP protocols. I will come up with these protocols in another article defining the same respectively. In this article I will talk about the Etherchannel Guard.

Fig 1.1- Etherchannel between the Switches

What is Etherchannel Guard ?
Etherchannel Guard is a way of finding out if one end of the EtherChannel is not configured properly. This could be that there are some parameters not matching up such as duplex and speed. Or it could be that one side is a trunk and the other isn’t. When there is a misconfiguration found, the switch will place the interfaces in error-disabled state and an error will be displayed.

You can use EtherChannel guard to detect an EtherChannel misconfiguration between the switch and a connected device. A misconfiguration can occur if the switch interfaces are configured in an EtherChannel, but the interfaces on the other device are not. A misconfiguration can also occur if the channel parameters are not the same at both ends of the EtherChannel

If the switch detects a misconfiguration on the other device, EtherChannel guard places the switch interfaces in the error-disabled state, and displays an error message. You can enable this feature by using the spanning-tree etherchannel guard misconfigure global configuration command