2801 fastethernet down

[Joli Martinez]

I have a 2801 router.  The Fa0/0 int shows up/down.  I have plugged it into diffrent cisco and non cisco switches and even a cross over cable to my laptop.  I cant seem to get the protocol up.  I have changed the speed to 100 and duplex to full to try to get it up that way and nothing.  This is what I have:

interface FastEthernet0/0

ip address 10.105.1.253 255.255.255.0

duplex auto

speed auto

again as you can see nothing out of the ordinary. any ideas?

[cadet alain · Accepted solution]

Hi,

router to switch is straight through cable, are you sure you selected the correct cable?

How are the the link leds when connecting the 2 ?

Regards.

Alain

[Joli Martinez]

yes,  2801 -> switch using straight through.  I have verified cable works.  and all light on both the router and the switch being plugged into are solid green.  Also verified the swith port works.

FYI.  I deleted all configs and all I have done so far is put an ip address on the FA0/0 int and did a no shut

when I do "ping 10.105.1.253 source fa0/0" from itself I get

Invalid source interface - IP not enabled or interface is down

and the 10 ip address is the one assigned to Fa0/0

same thing with loopback

r3#ping 127.0.0.1 source fastEthernet 0/0

% Invalid source interface - IP not enabled or interface is down

[cadet alain]

Hi,

if the interface is down then the ping won't work and there is no loopback( 127.x.x.x/8) on a router, this is on hosts for testing their tcp/ip stack.

But you marked the thread as resolved and it is not, why did you do so?

What about connecting f0/1? is it still the same to what type of switch port are you connected?

Regards.

Alain

[Joli Martinez]

I am having the same issue with fa0/1.  Blank config and all I am doing is giving the int an ip address. I know that i can ping 10.105.1.254 because I have connected my PC to the same switch and it works.  I have tried both setting the mode to trunk and to access and neither of them work?

any ideas?

[cadet alain]

Hi,

just to be sure:

sh ip int br on the router and sh int status on the switch

Regards.

Alain.

[Joli Martinez]

sh ip int brief on router shows up/down

sh ip int brief on switch shows up/up

[Joli Martinez]

sorry i found the problem.  After all this time.  The cable was bad.

lol

thx for the help.