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Trouble with T1

I am trying to set up a T1 link over a private fiber loop (aka telco not involved)I am told that the termination gear for the link itself provides no intelligence of any kind and I should treat it as back to back routers. I have carrier at both ends and yellow alarms. I have kept the default settings fro the Service modules set one side up as clock source internal and then entered the "clock rate 64000" interface command (which curiously does not show up under show run. Both routers are 2811's with wic-1DSU-T1-V2 wics. Attached is the output of "show service-module s0/0/0" showing many linecode and pathcode violations. I do not know what these errors mean so obviously I am not sure how to correct them. Both serial interfaces are down down also with the default HDLC encapsulation. Any direction would be most appreciated. I am also making the assumption that because I have CD that my wiring is correct. Is that a safe assumption?

Thanks in advance


Re: Trouble with T1

You do not need the clockrate interface command, though that is not your main problem. The clockrate command is needed only for synchronous serial V35 or RS232 interfaces.

The line code errors might indicate that the T1 transport equipment is set for AMI linecoding. Try changing the router settings to AMI and SF framing. AMI is seldom used today, and limits usable bandwidth to 56kb per channel.

service-module t1 linecode ami

service-module t1 framing sf

Your wiring might still be the problem. A T1 signal is very robust, and crossed pairs or broken wires can result in linecode and path code errors.