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need help with message "Fast Ethernet Line is up....protocol is down"

I can't find anywhere in my cisco books or on the web site for information on how to fix this. I have "no shut" in my configuration and it doesn't matter. I wiped out my startup-config and went into setup and when it asked if I wanted to configure the fast ethernet port I said yes and gave it an ip address of with subnet (default of and it said "line up and protocol up" and within 2 seconds without me doing anything, the message came up "line up, protocol down". I have a 2600 model router. any ideas?


Re: need help with message "Fast Ethernet Line is up....protocol

Does the router's fast ethernet speed and duplex settings match those of the switch it is connected to?

What does the switch 'show interface/show port' reveal?

Is the cable good (ie tested on other devices)?

Did you try a different port on the switch?

If it's for a lab and you only want the interface up/up, use the command 'no keepalive'.

Hope it helps.



Re: need help with message "Fast Ethernet Line is up....protocol

Thanks Steve...yes it is for just a lab and I don't have a switch connected to it. Although I do have a switch I will be hooking up to it. At that time, I will check the other parameters listed on the switch. Thanks again and I'll keep you informed. Regards, Bobt

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