HELP...1720 fastethernet problem

[jpelletier]

Hello everyone, we just bought a 1720 series router for a remote site, it's a 56k to the router, we use eigrp etc. The problem is the serial is up, up but the fastethernet0 is up, line protocol is down. The interface has an ip address, no ip directed broadcast and half-duplex that's it. I have used the very same configuration in 2 other routers without a problem EXCEPT the other routers use simple ethernet interfaces. This shouldn't cause it-please help if you can could it be the router? it's brand new?

[mljohnson]

It could be HW, but first a few things to check:

- disable keepalives (no keep); that should bring the line protocol up

- see if you can ping yourself

- confirm what the switch port is set up for; the 1720 will attempt to auto-detect the duplex (goes to half by default) and the speed; may want to try explicitely configuring these, same as the switch you are connected to.

- just in case, ensure that you have recent 12.1 or 12.2 IOS, last resort.

[jpelletier]

Excellent, it was the keepalives. I wish Cisco would put stuff like that in the info that came with the unit-but heh I'm happy it works-thanks alot good things happen to people who help others.

[jpelletier]

well the line protocol is now up but all of the packets output ie 189 are also output errors 189 any ideas?

[anderson-david]

doing no keepalive as mentioned before is just a test it keeps the interface up even if cable is pulled, try the rest of what the chap from cisco said ie confirming that your switch port duplex and speed settings match your routers ethernet port

hope this helps

[jpelletier]

Thanks for the input, in this case there is only one user now and a sole PC is terminated into the fastethernet port with a straight thru cable.

[o.hassairi]

if there's no HUB or switch between the PC & the router u must use a crossover cable and not a straightthru one