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New Member

Gateway clocking issue/cfg

I have a 2851 gateway with 8 T1 lines coming into it. They are a mix of PRI and CAS lines. 4 are going to the telco and 4 are used as tie lines to another PBX.

I have the following at the clocking cfg with the selects going to the telco lines:

network-clock-participate wic 0

network-clock-participate wic 1

network-clock-participate wic 2

network-clock-participate wic 3

network-clock-select 1 T1 0/0/0

network-clock-select 2 T1 0/0/1

network-clock-select 3 T1 0/1/0

network-clock-select 4 T1 0/1/1

On the tie lines, I am to provide clocking so on the controller interface for the tie lines, I set "clock source internal".

Then on the serial interfaces for the tie lines, I have "isdn protocol-emulate network"

I am getting some minor line issues on the tie lines and I was wondering if the above is correct. Did I miss anything? I would like to know if it's set up right before we go investigating the PBX system.



Re: Gateway clocking issue/cfg

It looks like you have the 2 port VWIC cards, are you getting errors on the second port of them? the x/x/1 port?

Keep in mind the VWIC-2MFT have 1 clock chip, so the second port might see slip second errors. You may be better putting one of the T1s w/internal clocking on each VWIC. This way you get around this possible clocking issue.

Can you post a 'show controller t1' so we can see what sorts of errors you're getting?

New Member

Re: Gateway clocking issue/cfg

See attached...

Re: Gateway clocking issue/cfg

The error count is low, are these going up still? Maybe they were due to setup/install/configuration work and are stable and clean of errors now. You can clear the controller counters and see if they increase.

Line Code Violations and Path Code violations are issues with the physical layer beyond the router usually. Check your cabling, the other devices configuration they are plugging into for the lines going to PBX. Also the cablelength is set to the default , if these T1s are < 133 feet from demarc or equipment they plug into I would change the cablelength to short 133 (smallest length setting).

New Member

Re: Gateway clocking issue/cfg

Eric - I have 5700 slip seconds on my controller. The T1 connects to a PBX. Clock source is line. The D channel has "isdn protocol emulate network". What if both sides are set up network.

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