Hi All,
I have some issues with incoming fax. The voice phase is successful but the switchover to fax fails. When I call the fax number it rings, connects, gives one short beep then is silent throughout the call until I drop the call.
ITSP SBC--> (SIP Trunk) ---> Cisco gateway --> (H323) ---> CallManager --> (SIP) ---> ATA 187 with latest sw version
On the gateway, when I make a call to the fax I can see the IOS MTP is in use for that call for about 6 seconds upon connect - G729 is used; the call does not change to passthrough codec. The ccm logs show the ATA sending an Invite to CallManager containing T38 in the SDP, but I don't see the T38 Invite being sent from the gateway to the SBC. Looks like it isn't switching from G729 codec to T38.
voice service voip
allow-connections h323 to h323
allow-connections h323 to sip
allow-connections sip to h323
allow-connections sip to sip
fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none
h323
no h225 timeout keepalive
h225 h245-address on-connect
sip
bind control source-interface GigabitEthernet0/0
bind media source-interface GigabitEthernet0/0
early-offer forced
!
dspfarm profile 3 mtp
codec pass-through
codec g729r8
maximum sessions software 250
associate application SCCP
!
The region on CallManager is also configured for G729.
Thanks
