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Community Member

clocking on router w/ two T1 lines

Hi, I have a a question about T1 clocking.

I have a 2620 router w/ a WIC T1 module connecting to a data T1 and a NM-HDV-1T1-12 going into a PBX. The WIC has clocking set for internal and is connected via a PPP line to another 2620 w/ clocking set to line. The 2620 on the far end is connected to a PBX via a tie line.

The issue is the voice line doesn't come up. The PBX is providing clocking at both ends to the VWIC. Can I set the VWIC at the near end to have clocking set line with the WIC set to clocking internal?

Thanks very much.


Community Member

Re: clocking on router w/ two T1 lines

I don't see any connection between the 2 sites PBX not coming up though it is the same problem - the T1 voice is not up( line is down).

Have you checked the wiring?

Note you have to create and RJ48( RJ45) cross connect. The transmit should go to the receive and visa versa.

Can you detail your cable pin outs.

Community Member

Re: clocking on router w/ two T1 lines

I had clocking problems with back to back routers using a T1 crossover. I use this configuration whenever I am receiving clock from the line.

network-clock-participate wic 0

network-clock-select 1 t1 0/0

and under controller t1 0/0

clock source line

Here is a link that describes these commands and what they do.

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