1760 Diagnostic Question

[sbhoward]

I have a 1760 Series Router with a Serial Interface that randomly goes up and down. According to our provider, they can find nothing wrong with the line.

It is configured with a single Ethernet WIC (E0), and a single WAN Wic Card (S0). Configurations have been checked and work well when card is up.

My question is shouldn't I be able to ping from one interface of the router to the other interface if the cards are functioning properly? ( from ethernet to serial?

When the system is down, I can telnet into the Ethernet port, but cannot ping to the WAN card in the same chassis?

I am assuming this is an error?

Thanks for any guidance....

[Richard Burts]

Steve

If I understand your message correctly I believe that your assumption is flawed.

I think you are saying that sometimes your serial interface goes down (when you do show interface the serial showes as interface up, interface protocol down). When any interface is in the up/down state it will not respond to ping - even from within the same chassis.

Depending on how the interface is configured there might be a number of things that could cause it to go down from time to time (some of which may be problems with the provider, some of them might reflect issues with the other end, etc.). If you want to provide some more specifics we might be able to make some suggestions.

HTH

Rick

[sbhoward]

You are correct. The show Interface command has both the Serial0.0 Down, line protocol is down message.

What sort of specifics can I provide? ( I really do suspect the provider) and this is fairly new equipment.

Thanks

[Richard Burts]

The first specific would be the complete configuration of the interface. (among other things this will tell us whether we are working with PPP, HDLC, Frame Relay, or whatever) Also it would be good to have the output of show interface. (if possible the output of show interface while the interface is up and then the output of show interface when the interface is down) It would also be helpful to have any messages that are in the log when something happens to the interface.

You might also tell us what the physical connection of the router physical interface is and what kind of circuit this is.

HTH

Rick