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E1 clocking issues

I have two E1s: one E1 connects to the PSTN and the other E1 connects to a PBX.

I found that I have Slip errors on the E1 that connects to the PBX. I used "network-clock-select wic 3" to use the clock of the E1 that connects to the PBX (which resides in a VWIC in slot 3). When I do that, the errors in the E1 to the PBX stop. However, I begin to have errors on the E1 that connects to the PSTN!

It seems that the PSTN and the PBX E1's require different clocking - but the router supports only one clocking (which it uses on both E1's).

How can I solve this E1 clocking issue?


New Member

Re: E1 clocking issues

Is the PBX expecting clocking from you or the PSTN ? If it is you i.e. the router then you just need to make the E1 that goes to the PBX to take it's clocking from internal. Make sue that the clock is OK with show network-clock for both the E1's & backplane. Other than that, you could try swapping the E1's over in case you have a faulty board/cable etc.

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