Calls dropping - need help

[dvdlots]

we have had reports of calls dropping for the last few months and i am tearing whats left of my hair out trying to get to the bottom of it. We have an Avaya Gs3i PBX running R11. We had an engineer onsite for a full day monitoring alarms etc and he found no problems. Our network provider have said there is no problems also so i started looking at the alarms on our PBX myself.

I have ruled out all of the 15 present alarms bar 1 error, an ISDN-SGR err type 3878 Aux Data 6660. I have managed to find the error code in an avaya manual that states it is a network issue and to contact our network provider. I am a bit reluctatnt to do this as I don't feel this is definately the issue as I can find no reference to Aux Data 6660 for this error code.

I've ran test commands on all our trunks, ISDN ports etc but to no avail, all passed correctly.

Can anybody help me out here please???

 

[mikeydidit]

If the signaling group is having problems, that would be where I would start. If you loose the your primary D signaling thet rest are dumb and wont work. It could be a problem with that span. Something you may want to consider is to also have a seconday D channel. This would provide a backup. Try the "test sig ?" (what ever the sig # is). See what the results are.

Let me know if you need more help.

"Wise men speak because they have something to say; Fools because they have to say something."
(Plato)

 

[dvdlots]

thanks mikey

we actually have 3 ISDN-PRI's so we have plenty of backup. not all users are reporting dropped calls at the same time but it is random. i ran the test sig on our second line as this is where the error is occuring more reularly but it also occurs on our other 2 lines less frequently.

TEST SIG 2 Results:-
PORT Maintenance Name Test No. Result Error code
2 ISDN-SGR 636 PASS
2 ISDN-SGR 639 ABORT 1132
2 ISDN-SGR 637 PASS
2 ISDN-SGR 647 PASS

not sure why it aborted test 639? Would this cause dropped calls?

 

[mikeydidit]

If these are the same group and using the single D channel, it controls all the trunks. If you use the "disp sig ?" command it will tell you what the D channel is controling. If these all have their own signaling group, then that should narrow it down.

"Wise men speak because they have something to say; Fools because they have to say something."
(Plato)

 

[dvdlots]

each signaling group uses a different d-channel port (primary D-channel = 01A14xx etc.). where does this lead me to?

 

[mikeydidit]

If these trunks use the 24 member as the signaling for each span, then you can narrow this down to which trunks you are having the problems with. The signaling group you are having problems with in this case will only effect the other 23 members. After having problems like this myself in the past I would look at the T-1 equipment (smartcard)coming in from your vendor. You can remove these trunks from your group and test with them.

"Wise men speak because they have something to say; Fools because they have to say something."
(Plato)

 

[dvdlots]

thanks for all the help mikey, I think it's time i handed this back to our vendor.

BTW the trunks use the 16 port on all 3 d-channels.