Troubleshooting Voice Gateway incoming issue when using ISDN

If the incoming call is getting disconnected with the message "The call cannot be connected" then mostly it could be because of the IVR down issue.
To troubleshoot the same first enable the debug "debug isdn q931" on the voice gateway. See if you are seeing any cause for the call disconnection.


045951: Feb  4 02:38:28.074: ISDN Se0/0/0:23 Q931: SETUP pd = 8  callref = 0x1943
Bearer Capability i = 0x8090A2
Standard = CCITT
Transfer Capability = Speech 
Transfer Mode = Circuit
Transfer Rate = 64 kbit/s
Channel ID i = 0xA98381
Exclusive, Channel 1
Progress Ind i = 0x8283 - Origination address is non-ISDN 
Calling Party Number i = 0x1180, '919902384363'
Plan:ISDN, Type:International
Called Party Number i = 0xA1, '--------------'
Plan:ISDN, Type:National
045953: Feb  4 02:38:28.074: ISDN Se0/0/0:23 Q931: Received SETUP  callref = 0x9943 callID = 0x221B switch = primary-ni interface = User
045954: Feb  4 02:38:28.078: ISDN Se0/0/0:23 SERROR: process_pri_simple: NO name in GTD
 --More--         045955: Feb  4 02:38:28.082: ISDN Se0/0/0:23 Q921: User TX -> INFO sapi=0 tei=0, ns=29 nr=1
045956: Feb  4 02:38:28.082: ISDN Se0/0/0:23 Q931: CALL_PROC pd = 8  callref = 0x9943
Channel ID i = 0xA98381
Exclusive, Channel 1
045959: Feb  4 02:38:28.322: ISDN Se0/0/0:23 Q931: DISCONNECT pd = 8  callref = 0x9943
Cause i = 0x8081 - Unallocated/unassigned number


The above casue indicates that there is some issue with called party number.

Check where the incoing call lands:

Check the incoming calls translations configuration on done properly or not.
The easiest way to do this is enable "debug dialpeer" on the vgw and see if it through any errors.
or check the voice-port configuration for incoming call translation rule name using the "show run | sec voice-port <port number>"

voice-port 0/0/0:23
 translation-profile incoming pstn-in
 timeouts call-disconnect 5


Then check the translation-profile and respective translation rule for the pstn-in.
This will show you the extension number where the call lands after the translation. This may be your IVR system extension number.
check the status of your IVR system.


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