Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

C1841 fa0/0 up when unplug LAN cable

When I unplug LAN cable from interface fa0/0 why interface still up but protocol down ?

It is default ? or we can set ?

Thank you in advance.

  • LAN Switching and Routing
2 ACCEPTED SOLUTIONS

Accepted Solutions
Green

Re: C1841 fa0/0 up when unplug LAN cable

If you have keepalives disabled, then the link will stay up.

Check your config, under that interface, for a "no keepalive" statement

Also make sure you are looking at the right interface ....

Good Luck

Scott

Hall of Fame Super Silver

Re: C1841 fa0/0 up when unplug LAN cable

teerapon

It is the default behavior of IOS routers such as the 1841 that if the FastEthernet interface is not plugged into some device then the interface will show as interface up and line protocol is down.

HTH

Rick

3 REPLIES
Green

Re: C1841 fa0/0 up when unplug LAN cable

If you have keepalives disabled, then the link will stay up.

Check your config, under that interface, for a "no keepalive" statement

Also make sure you are looking at the right interface ....

Good Luck

Scott

New Member

Re: C1841 fa0/0 up when unplug LAN cable

Thank you Scott.

So, If I used "no keepalive" command under int fa0/0, interface and protocol will up both but I did not plug LAN cable into that interface.

I also check with another new router C1841. After completed boot and no shutdown the fastEthernet interface. FastEthernet interface is up without LAN cable connected.

It may be default of router? and How to make it down when we did not plug the LAN cable into interface ?

Environment

C1841

IOS c1841-ipbasek9-mz.124-23.bin

Thank you.

Hall of Fame Super Silver

Re: C1841 fa0/0 up when unplug LAN cable

teerapon

It is the default behavior of IOS routers such as the 1841 that if the FastEthernet interface is not plugged into some device then the interface will show as interface up and line protocol is down.

HTH

Rick

227
Views
0
Helpful
3
Replies
This widget could not be displayed.