It sounds like ATT is assuming the voice traffic is VOIP. The ESU is MUXing out the channels from the T1 for the data and the voice so there is no priority to set on the ESU. I look forward to seeing what the tech finds on the PBX side. Hopefully we can verify if it's seeing AIS alarms.
NEC tech change the E1 / T1 card into PBX .... We clear the alarm history into ESU .... and start from there,
we invite user to make calls and if any drop, they will let us know so ASAP.
ALL GOING SMOOTH AND PERFECT .... and suddenly ... CHAOSS
Calls drop, over and over again ...
Into ESU at Status / View History we got this results
1:26pm - 04/03 - 0.2 Remote Alarm
1:26pm - 04/03 - 0.2 Remote Alarm Clr
1:30pm - 04/03 - 0.2 Remote Alarm
1:26pm - 04/03 - 0.2 Remote Alarm Clr
1:30pm - 04/03 - NI Frame Slip
1:30pm - 04/03 - NI Frame Slip Clr
1:40pm - 04/03 - 0.2 TS16MF Loss Clr
2:11pm - 04/03 - NI Frame Slip
2:11pm - 04/03 - NI Frame Slip Clr
2:11pm - 04/03 - 0.2 Remote Alarm
2:11pm - 04/03 - 0.2 Remote Alarm Clr
2:18pm - 04/03 - 0.2 Remote Alarm
2:18pm - 04/03 - 0.2 Remote Alarm Clr
2:18pm - 04/03 - NI Frame Slip
2:18pm - 04/03 - NI Frame Slip Clr
2:43pm - 04/03 - 0.2 Remote Alarm
2:43pm - 04/03 - 0.2 Remote Alarm Clr
2:43pm - 04/03 - NI Frame Slip
2:43pm - 04/03 - NI Frame Slip Clr
3:07pm - 04/03 - NI Frame Slip
A remote alarm on the 0.2 suggests there was an alarm on the line going to the PBX. Did the tech see any errors on the PBX side? When it was going smoothly, were calls going through with no problem?
If you have no bypassed the ESU yet for testing purposes, I'll recommend it again. Based on the photo both sides of the connection use coax cables and since the ESU will just be muxing out certain channels for the PBX, the PBX should be able to make calls on the E1 when it's plugged in directly.
NEC Tech guys get and his program, this report ...
(Remote Site = 01)
Data = (01 FF FF FF FF FF FF FF)
DTI line failure.
Power Failure Kind : AIS error
Data = (F3 FF FF FF FF FF FF FF)
Calls were made from around hour and half and not problems at all. Suddenly drops calls.
I talk with NEC tech guy regarding doing that. Bypass ESU and he don't recommend it. He explain to me about signaling differences beetwen US and MX.
and thats why he doesn't recommend it.
What about this errors ....
0.2 TS16MF Loss Clr & NI Frame Slip mean something important for this kind of problems .. ???
BTW and going crazy right now .....
Do you think if i change the 2 COAX patch cord going from PBX into ESU, could make any significant change ....I mean the actual ones are very ... thin .....
It could not hurt to replace the coax cables, but I would not expect cables to lead to an AIS error. But it could relate to a power failure and the AIS looks like it's coming from the PBX.
The ESU muxes out E1s, so the signaling it likely to be the same on both sides. You should be able to look under Config in the ESU and check the Network (NI) and Port (0.2 Drop) and see if the NFAS word, CAS/TS16, and CRC-4 are all set the same. If they are the same for both ports, then the E1 can connect to the PBX.
Take a look at the NI Perf Reports and NI Errors the next time the problem comes up, and the Port Status 0.2 as well.
We change the 2 COAX patch cords from the E1 BNC to DB15 Adapter to E1 card into PBX..
Also we change into Config / Network (NI) / Interface from 120 Ohm bal to 75 Ohm Bal.
But i got a question ... regarding E1 BNC to DB-15 Adapter ....
Right now both dip switches are down .... so we match that with the change made below.
Do this change could mean anything for the problem we have ....??
Just staring watching at the computer room the ESU, suddenly i got alarms into CSU and DSU / DROP
Into Status / Port Status / Drop Errors
I got asterisk into BPV / SLIP / FER the one named CRC its blank.
What alarms do you see in the alarm history? And on the Network side do you see errors under NI Perf Rpts? I would normally expect a hardware issue with the ESU to show persistent errors or alarms, not for it to come and go. The drop port was showing Bipolar Violations, clock slips, and framing errors. So if we had alarms on both sides of the ESU, we want to see where we were receiving an alarm and where we were transmitting an alarm.
I'm not sure about the dip switches, are they on the adapter? The ESU 120 has no dip switches, so I'm not sure what a change in the switches would represent.
The dip switches are into the adapter, on both sides.
At the alarm history we got
- 0.2 Remote Alarm
- 0.2 Remote Alarm Clr
- NI Frame Slip
- NI Frame Slip Clr
Under NI Perf Rpts no errors at all.
Could be all this behavior at hardware failure at the ESU ?
So, what we're seeing at the time the trouble comes up is an alarm from the PBX. Based on the information from the PBX vendor, there is an AIS alarm at that time. It could be a hardware issue with the ESU. It could also be a hardware issue with the PBX. The best way to test that will still be to plug the E1 straight into the PBX for testing purposes and see if the the problem persists or goes away.