Cisco IOS – An interface whose trunk encapsulation is “Auto” can not be configured to “trunk” mode.
Mar19

Cisco IOS – An interface whose trunk encapsulation is “Auto” can not be configured to “trunk” mode.

KB ID0001167 Problem If you try and change a ports status, to make it a trunk port, you may see this error; Petes-Switch(config-if)#switchport mode trunk Command rejected: An interface whose trunk encapsulation is “Auto” can not be configured to “trunk” mode. Trunk Settings I don’t know if this is a throwback to when we had ISL trunking and 802.1q, but you need to specify the encapsulation before you can...

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Cisco ASA 5500 – Sub Interfaces and VLANS
Nov17

Cisco ASA 5500 – Sub Interfaces and VLANS

KB ID 0001085  Problem You can take the physical interface of a Cisco ASA firewall, (or an ether channel) and split it down into further sub-interfaces. This way you can set multiple VLANs to use this interface as a gateway at the same time whilst still separating the traffic. In this scenario I’m going to have two VLANs, one for my wired clients, and one for a ‘Guest WiFi’ that I’m setting up. I want the guest...

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