Avaya & Cisco Intergation strang random Issue

[t-alkhalidi]

hi Expertise,

i have integrated Cisco call manager 4.1 with AVaya communication manager through 2 E1 QSIG line. in addition to that Cisco terminate the PSTN lines so a user in Avaya can call out using the PRI lines on cisco router. i can ext to ext both ways with calling number and name.

the weired issue thatin rush hour a user call from Avaya get failed somtimes and getting error tone . he hangup and try call again it works. and this is only happening in rush hour. check the trunk between avaya and Cisco to see if all lines busy , and i found 20 channels still free and can be used. avaya traces shows that Cisco is refusing the call somtimes.

any help or idea from expert in this here. or how to troubleshoot in cisco side. avaya traces and errors shows call rejected by cisco so network out of order temporarly.

any idea experts? its really challenge case

[t-alkhalidi]

Is it synchronization issue or DSP resources? I have 2 E1for QSIG integration and another 2 PRI for PSTN on Cisco router. So total 4 PRI on Cisco router. How do I set up synchronization? I still don't get the concept of synchronization from document. When I need to setup the clock for each of them in this case.

Which PRI do I need to do as make main clock source on Cisco? And why?.

How to trace and analyze a call on Cisco ? how to trouble shooting it. A lot of calls on the system and I want specifically trace the call to see the error .

Cisco phones make the calls with no issue. Only from Avaya side we face the issue and not all lines busy between the 2 systems.

[t-alkhalidi]

any idea please