Serial interface says line down, protocol down

i have a serial interface that says down, down. I have looked at both routers and the encapsulation is correct. The one router says s1 is up, up and the only thing configured on it is the ip. on the other router the s1 interface is down, down. I was always led to believe this is a physical problem with the cable or the interface itself but I was told to check my config. it is not administratively down either. Any thoughts would be great!

THX!

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Comments

jjbrog

clock rate on dce side?

ziggi138

I would replace the cable with a known good one. if that doesnt fix it, i have no clue. if there was no clock rate it would show line up protocol down. The only way i have been able to get a down/down status that was not administratively down is by unplugging the cable.

N3tWrkNut

Thanks for the replies. It was the cable! I did a sh controller serial 1 and it said no cable!

jjbrog

Thats for the correction ziggy, I should have known better, goes to show to look at a question better for the exam, lol

As a side note, I thought i had the same issue ones when i first started out. Turned out I didn't know that a csu/dsu showed up as a serial interface, was trying for awile to figure out wtf was wrong, lol