NBX v5000
v6.0.59


We just backed out of a cutover to a new voice provider (TW Telecom) because outgoing calls over the new T1 circuit didn't have any audio (no ringing - nothing). The tech at the NOC reported a good connection and could see the calls going out. Our T1 card is working fine with our current provider. That said, the existing line is a "true" T1/PRI while the new line is created off the back side of a Cisco router (our building is on TWT fiber).

Has anyone run into this issue? If so, any guidance?

I've added a second T1 card to our chassis and connected the new T1 to that. If we can get that one configured and running, we'll just shut down the existing one.

thanks in advance,
Dave

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Originally posted by: cknipe
Have you tried connecting with a t1 crossover cable? A typical t1 uses pairs 1,2,4, and 5. Most of the routers that have a pri like this have required me to use a t1 crossover cable. hope this helps.

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Yep. T1 crossover cable was required to get a link. Link status lights show all is good - but I'll double check the wiring, just in case.

Dave

Thanks for the loopback tutorial. Learn something new every day!

quote:

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Originally posted by: cknipe
Im assuming you guys have the line coding (b8zs) and all of that double and triple checked?

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Yep. And, as I mentioned, the existing card was working great with the "true" T1/PRI from our soon-to-be-former carrier.

2nd card is showing "Nominal" when connected to their router.

quote:

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Originally posted by: cknipe
Its starting to sound like telco to tell you the truth. I was once on a project with TW telecom and they kept pointing the finger at us for the longest time. Then 3 months later, they finally figured out that they had a port speed set to half duplex on one of thier routers. just my .02

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Half duplex seems like it could cause this. About the only advance Tech Info they provided was to make sure everything at OUR end was configured at 100/FD. I've rebuilt our NBX several times and am comfortable at the majority of Admin tasks, but can get lost in the Telco-lingo. Sounds like we're going to have to bring in a consultant (at our cost) to troubleshoot this. If it turns out to be their mixup, I'm gonna expect them to cover the expense.

Dave

awesome. glad to hear it works. fat chance on getting them to cover the costs of your tech but hopefully they'll give at least a service credit. Im the same way with the tech lingo. The telco too offten that not will just have thier techs run thier tool to check something and if it comes back "green" then they blame it on the pbx. Those people never think outside the box. and then they leave it up to you to prove to them with $10,000 tbird tools that you dont own that they are at fault.

If you dont own the tools, keep in mind 90% of the circuits out there are going to be a PRi with b8zs and NI2 with the telco sending you 4 digits inbound. In fact my office is like that too. If im lucky enough to have the equipment a few days prior to going onsite, you can always build it inhouse and test on your own circuit for a few test calls.