newb question

OK I just got some free equipment from work and I ordered a couple things off eBay. I have kind of been a packet tracer junkie so far so I don't have much experience hooking stuff up.

Problem
I have 2 2501 routers hooked up with a dce/dte cable. I have set the ip on both interfaces,run the no shut command and set the clock rate on the dce end to 64000.Both interfaces are using default encapsulation but I cannot ping ether interface from there respected routers. A sh int s0 command of course shows the line prot down. What am I doing wrong here? I feel like a complete nub

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Comments

fly351

Do a "show ip int brief" on both routers and tell us what they say.

alan2308

The first thing I would do is double check the connections. Do you have another cable you can try? Try "show cdp neighbors" on each router. Can they see one another?

wbosher

How about posting the sh interface output. I agree with alan2308, sounds like a faulty cable/interface or bad connection.

Sounds silly, but have you tried wiggling the connections? Might not be in properly, sure you've tried that already though.

Try "show cdp neighbors" on each router. Can they see one another?

If the line protocol is down, I don't think the routers will be able to see each other using the "show cdp neighbors" command.

spartangtr

When this happened to me it was a bad DCE/DTE cable.

VAHokie56

here are the outputs

ROUTERA#sh int s0
Serial0 is down, line protocol is down
Hardware is HD64570
Internet address is 172.17.1.1/30
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation HDLC, loopback not set, keepalive set (10 sec)
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/64/0 (size/threshold/drops)
Conversations 0/0 (active/max active)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 9 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=down DSR=down DTR=down RTS=down CTS=down

ROUTERB#sh int s0
Serial0 is down, line protocol is down
Hardware is HD64570
Internet address is 172.17.1.2/30
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation HDLC, loopback not set, keepalive set (10 sec)
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/64/0 (size/threshold/drops)
Conversations 0/0 (active/max active)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 10 interface resets
0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=down DSR=down DTR=down RTS=down CTS=down

Monkerz

Cabling\Interface Problem. You sure you have the DCE connected to the correct router's interface?

fly351

VAHokie56 wrote: »

here are the outputs

ROUTERA#sh int s0
Serial0 is down, line protocol is down

ROUTERB#sh int s0
Serial0 is down, line protocol is down

Yep, like the others said, you need to check your cabling first

wbosher

Might be a bit of a pain at the moment, but you don't get to learn this sort of thing using a simulator eh?

Deathgomper

You did make sure to do a "no shut" on the interface after you applied the ip address and mask?

Selfmade

sounds like a layer 1 problem to me, i suggest what everyone else suggested, so my suggestion is to repeat their suggestion that you try different cables to eliminate cables as the problem, the interfaces can be faulty, but the probability of that is very low.

also remember once you connect them and configure, remember no shut and to set the correct clock rate on both ends.

fly351

Deathgomper wrote: »

You did make sure to do a "no shut" on the interface after you applied the ip address and mask?

hmm since when does this matter?

alan2308

fly351 wrote: »

hmm since when does this matter?

It depends on the router and the IOS, but sometimes you have to shut/no shut after making changes to an interfaces config for it to take effect.

networker050184

alan2308 wrote: »

It depends on the router and the IOS, but sometimes you have to shut/no shut after making changes to an interfaces config for it to take effect.

I've never seen this to be the case on any router or interface I've ever worked on. Do you have an example?

alan2308

networker050184 wrote: »

I've never seen this to be the case on any router or interface I've ever worked on. Do you have an example?

Not off hand, no. I could also be completely out in left field on this one (it has happened a time or two before

VAHokie56

Thanks for all the help. I am to the point now where both interfaces will stay up for a second then drop...I guess its just a bad cable, I ordered a new one

Deathgomper

fly351 wrote: »

hmm since when does this matter?

I was thinking that rebuilding a config file would cause this but after spending some time in my lab I stand corrected. The ports will be shown as "Administratively down" instead of just "down" in my scenerio.

fly351

Deathgomper wrote: »

The ports will be shown as "Administratively down" instead of just "down" in my scenerio.

Thats what I was pointing out

alan- if you happen to find some info on what you stated, I would be interested in reading it

I never heard/seen that before.

VAHokie56

Ok revisting this one more time . Got new cables ...same issue , I have narrowed it down to being an issue with just one of the routers. Regardless of what serial int I use it will go line protocol up for about 10 seconds then drop back down ( and weither I switch up the cables and use the clock rate command on ether one) So I guess its just a bunk router with bad serial interfaces? and suggestions before I just it as a foot rest?

thehourman

OMG I had the same experience! Have you read my short thread about this up/up state for a few secs and then it goes up/down.
I had a bad module at the time, and the dude, who sold it to me hasn't returned my module nor my faulty module.

Delirious

How bout doing a show controllers serial [slot/port]

Should look like the below (last line in the example is what we need) and will tell you if the serial port is even detecting the cable correctly. Have you tried using the other serial ports on the router?

MK5 unit 0, NIM slot 1, NIM type code 7, NIM version 1
idb = 0x6150, driver structure at 0x34A878, regaddr = 0x8100300
IB at 0x6045500: mode=0x0108, local_addr=0, remote_addr=0
N1=1524, N2=1, scaler=100, T1=1000, T3=2000, TP=1
buffer size 1524

DTE V.35 serial cable attached

wbosher

I think I remember reading somewhere that sometimes a buggy IOS can cause interface problems. Have you tried putting the IOS from your good router, onto the bad one? Probably won't make any difference, but worth a try.