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No busy signal when calling from PSTN


Good day!

I have problem with working of inbound calls from PSTN. When caller dial busy phone, his hear silence instead of busy tone.

I use following scheme:

PSTN>Cisco 2921>CUCM 7.1 + CCX 7.0.2

PSTN user call number 22xxxx, this number translte on Cisco 2921 to 2052 - CCX route point. When call place to 2052 CCX application (script) starts and PSTN user dial additional number 1065. If another PSTN user try to call number 1065 at the same time, his hear silence instead of busy signal.

I think problem with signaling, but I dont no how resolve it.

Any Ideas?



Are you using SIP or H323 between the 2921 to CUCM?  Also beside not hearing busy tone, do you hear any ring back tone at all?

If you are using H323, could you please try the configs below:

! VoIP dial-peer to the CUCM


dial-peer voice 100 voip

destination-pattern 2052

progress_ind setup enable 3    <--- add this line

! POTS dial-peer to the PSTN


dial-peer voice 999 pots

tone ringback alert-no-PI      <--- add this line

Good day, Victor,

Thank you for your participation!

The problem was in the CCX application - script worked incorrectly.Correction of the script solved the problem.

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