Strange problem with 4xPRI

Hello.

Now i’ve got configuration like this:

PSTN ==== 2xE1 ==== Asterisk box ===== 2xE1 ===== Nortel Meridian

Asterisk box: 2xXeon 2.4Hz, TE410P + ~20 voip phones by sip
PSTN: I think Alcatel station
Nortel: 2xNTBK50AA

Before i installed asterisk - PSTN and Nortel were connected directly (each of them is black box for me).

Now i’ve got the annoying me strange problem - * cant bridge more than 30 calls. When count of calls approximate to 30 (and ZAP channels approximate to 60) i see messages like this (on console and in pri debug file):

!! Got reject for frame 116, retransmitting frame 116 now, updating n_r!
!! Got reject for frame 116, retransmitting frame 117 now, updating n_r!
!! Got reject for frame 116, retransmitting frame 118 now, updating n_r!
!! Got reject for frame 116, retransmitting frame 119 now, updating n_r!

some other messages:

!! Got reject for frame 15, but we only have others!
!! Got reject for frame 45, retransmitting frame 45 now, updating n_r!
!! Got reject for frame 45, retransmitting frame 46 now, updating n_r!
!! Got reject for frame 101, but we only have others!
!! Got reject for frame 109, retransmitting frame 109 now, updating n_r!
!! Got reject for frame 109, retransmitting frame 110 now, updating n_r!
!! Got reject for frame 109, retransmitting frame 111 now, updating n_r!
!! Got reject for frame 109, retransmitting frame 112 now, updating n_r!
!! Got reject for frame 109, retransmitting frame 113 now, updating n_r!
!! Got reject for frame 109, retransmitting frame 114 now, updating n_r!
!! Got reject for frame 109, retransmitting frame 115 now, updating n_r!
!! Got reject for frame 116, but we only have others!

After this messages count of calls go down (hangup possible).

There arent this messages when count of calls less than 25.

And i couldnt have count of bridged calls between PSTN and Nortel more than 30 The structure of calls - 90% outbound (Nortel->PSTN), 8% inbound(PSTN->Nortel), 2% - VoIP (SIP->PSTN,SIP->Nortel)

What that CAN be? Thank a lot for any ideas!

zaptel.conf (span 1,2 - Nortel, span 3,4 - PSTN)

span=1,0,0,ccs,hdb3
bchan=1-15,17-31
dchan=16

span=2,0,0,ccs,hdb3
bchan=32-46,48-62
dchan=47

span=3,1,1,ccs,hdb3
bchan=63-77,79-93
dchan=78

span=4,2,1,ccs,hdb3
bchan=94-108,110-124
dchan=109

zapata.conf

[channels]

language=en
priindication = outofband
resetinterval = 86400
facilityenable = yes
usecallerid=yes
callwaitingcallerid=yes
threewaycalling=yes
rxwink=300
transfer=yes
canpark=yes
cancallforward=yes
callreturn=yes
echocancel=yes
echocancelwhenbridged=yes
echotraining=yes
callgroup=1
pickupgroup=1
immediate=no
switchtype=euroisdn

rxgain=1.0
txgain=-6.0
group=1
context=nortel
signalling=pri_net
channel=>1-15
channel=>17-31
channel=>32-46
channel=>48-62

group=2
callerid=9330139
signalling=pri_cpe
context=pstn
channel=>63-77
channel=>79-93
channel=>94-108
channel=>110-124

perhaps a timing issue with the PRIs? I think you may need to use a timing cable to keep the same timing source both on the telco PRI and pbx PRI… not sure on that one though…

Hi
For this type of problem you need to do two things.

  1. enable pri debugging. and post the output. (edited)

2 Get an ISDN tester and monitor the link on both sides and see whats happening.

One thing to try is disabling echo canceling and see what happens