#8 : IP Phone doesn’t hangup an outbound call, when external user hangup first

Posted: March 21, 2014 in Collaboration


I have issue with the Outbound Calls to External PSTN phones or Mobiles, when they hangup first- the IP phone does not hangup automatically, instead beeps saying “the other person has hangup”.

This only happens to Outbound calls, the same caller (mobile or PSTN) calling in and disconnecting first will be followed by IP phone hanging up automatically without needing to put the IP phone down manually.

I have a feeling this is outbound POTS dial peer config issue

Scenario & Analysis:

Call Flow: CallManager with H323 Gateway -ISDN E1 solution

The debug Isdn q931 command output shows this message when the Public Switched Telephone Network (PSTN) user hangs up the call:

ISDN Se1/0:15 Q931: call_disc: PI received in disconnect; Postpone sending RELEASE for callid 0x8012

Possible Csuses & Solutions:

This could be due to ISDN PI message.

Issue this command in global configuration mode

voice call disc-pi-off


voice call disc-pi-off :- This command is used to enable the gateway to treat a disconnect message with progress indicator (PI) like a standard disconnect without a PI, use the voice call disc-pi-off command in global configuration mode. To reset to the default, use the no form of this command.

Gateway disconnects incoming call leg when it receives a disconnect message with PI. This command was integrated into Cisco IOS Release 12.3(7)T.

Use this command if the gateway is connected to a switch that sends a release immediately after it receives a Disconnect with PI. To properly handle the call, the switch should open a backward voice path and keep the call active. Otherwise the rotary dial peer feature does not work because the incoming call leg is disconnected.

Using this command enables the gateway to handle a disconnect with PI like a regular disconnect message so that you can use the rotary dial peer feature.

**# If you have more info/query on this, let others know of it. #knowledge- more you give, more you gain. :)</span

  1. Sajid says:


    I am facing similar issue. Call does not disconnect when called party hangs the call. ISDN/E1 shows a release message coming from teleco but this release/disconnect msg is not passing to SIP server hence call is still showing in active state.

    When call disconnects from called party, I get below release msg from teleco:
    Cause i = 0x8090 – Normal call clearing
    *Mar 1 00:07:01.527: ISDN Se1/0:15 Q931: TX -> RELEASE pd = 8 callref = 0x0082
    *Mar 1 00:07:01.647: ISDN Se1/0:15 Q931: RX <- RELEASE_COMP pd = 8 callref = 0x8082

    But my SIP server and IP-phone is not disconnecting the call. I am not getting any BYE msg from CISCO.

    Please advise!

    Thank you in advance!




  2. bkanhatti says:

    Have you tried disabling the pi bit on gateway and checked if it’s forwarding hangup msg from teleco to server ?


  3. Sajid says:

    Hi bkanhatti,

    Do you mean disabling voice call disc-pi-off ? It does not make any different by using this command or without.




  4. I’ve added this “voice call disc-pi-off” into GW config, but its not working. Could you please help me on this?


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