What does protocol down mean

This is what we are looking for. At least we now know that there are no cable, speed or duplex errors. Hmm it says err-disabled. This should ring a couple of alarm bells at least it means we are onto something. Use the show interfaces status err-disabled command to see why the interface got into error-disabled mode. We can look at the port security configuration and we see that only 1 MAC address is allowed.

The last MAC address seen on the interface is c. If you like to keep on reading, Become a Member Now! Here is why:. Tags: Troubleshooting. I still have other vlans of a wide open class b such as Please note: there are other class b vlans in play still.

Would this booger anything up on me? Once that is done, do a "sh vlan brief" again. Make sure you have no ports configured for the VLAN you want to destroy Jfrapp I tried connecting a laptop to the switch and telling a port to go to vlan , no shutdown There are still ports on the router configged for vlan 18 though.

I wonder if leaving the ports configged is screwing things up. You've created an SVI vlan interface without creating the layer 2 vlan for it to sit on, hence it won't come up.

Then go check interface vlan , should be up, and You can now assign interfaces to the vlan and give hosts IPs in that subnet with the default gateway of To bring the newly created SVI interfaces up.

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Create a free Team What is Teams? Learn more. What can cause "FastEthernet is up, line protocol is down" on a Cisco Switch? Ask Question. Asked 6 years, 9 months ago. Active 3 years, 1 month ago. Viewed k times. In other words, Is the cable that is connected to the local interface, but not connected to the far end switch causing this situation? Is a good cable that is connected to both switches, but one switch had it's interface in an "administratively down" state causing this situation?

If not, what would cause an interface to be in an up,down state? Improve this question. Kevin Bowen 1 1 gold badge 4 4 silver badges 12 12 bronze badges. Asked 10 years, 1 month ago. Active 3 years ago. Viewed 62k times. Improve this question. Hennes Rayne Rayne 2 2 gold badges 11 11 silver badges 22 22 bronze badges. That'll mark the question as solved in the system. Add a comment. Active Oldest Votes.

Improve this answer. Theo Theo 1, 11 11 silver badges 12 12 bronze badges. This might be a very late reply but here's what I understood so far: The interface status has two parts to it: the interface up or down the line protocol up or down.