Voice gateway SPA8000 problem sending faxes.

[Olzhas1986]

Hello, I am a representative of the corporation Kazakhmys using the whole range of your devices. The problem is as follows: Voice Gateway Cisco SPA 8000 does not send faxes to voice gateway Grandstream GXW4232. The problem occurs only if the two voice gateways work with each other. The call comes to the SPA 8000, but after lifting the handset, the session immediately reset. What settings I need to change?

[Dan Lukes]

Note that official Cisco's support can be contacted here. This WWW is discussion forum where volunteers may help you. But it require exact technical description of the issue you have.

Disclose your's current configuration. Catch SIP session in question. Turn on syslog&debug and catch them as well. Then we may try to do our best to help you.

[Olzhas1986]

Ok! 

Something wrong in the debug, but i am not sure what. Would you help me please, what is wrong?

The debug in application.

Thanks a lot.

[Dan Lukes]

It seems you have RTP packet Size set to 30ms. It's not optimal even for voice call. You should not exceed 20ms for voice, for the fax I propose you to use 10ms.

Note it may not solve your problem, but it increase reliability of fax session.

But now back to the issue. If I understand correctly, the attached log has been captured on

Cisco-SIPGateway/IOS-15.2.4.M7

OK. It seem that most important line of such log is:

068963: Feb 24 05:50:16.778: //6170583/D6D178518A93/CCAPI/cc_api_call_disconnect_done:
   Disposition=0, Interface=0x160DE9D8, Tag=0x0, Call Id=6170583,
   Call Entry(Disconnect Cause=3, Voice Class Cause Code=0, Retry Count=0)

If I understand correctly the log, the call has been terminated by SIP Gateway.

I see no apparent issue with ATA8000 (not counting the Packet Size value mentioned on top). There is a problem with SIP Gateway. Unfortunately, I'm not expert on the matter nor this forum is best forum for question related to SIP Gateway. You should ask on IP Telephony forum instead.