11-10-2011 07:21 AM - edited 03-04-2019 02:13 PM
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?
Solved! Go to Solution.
11-10-2011 08:05 AM
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
11-10-2011 08:05 AM
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
11-10-2011 08:13 AM
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
11-10-2011 10:40 AM
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
11-10-2011 01:11 PM
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?
11-10-2011 01:40 PM
Hi,
just to be sure:
sh ip int br on the router and sh int status on the switch
Regards.
Alain.
11-10-2011 05:28 PM
sh ip int brief on router shows up/down
sh ip int brief on switch shows up/up
11-10-2011 05:32 PM
sorry i found the problem. After all this time. The cable was bad.
lol
thx for the help.
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