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Caller ID Unkown Number with FXO [random]



I have a Voice gw 2921 with IOS 15.1M with cucm 8.6

Calls will go through VIC2-4FXO card. the voice gateway is configured as h323 with the CUCM

The problem is that Incoming calls sometimes display the calling number and sometimes display "Unknown Number"


Voice port configuration is as follow

voice-port 0/2/1
 no battery-reversal
 cptone NL
 connection plar opx 114
 impedance complex2
 caller-id enable
 caller-id alerting line-reversal
 caller-id alerting dsp-pre-allocate


I tried 3 different IOSs

I noticed that I receive this mssg in debug when I got Uknown Number : htsp_stop_caller_id_rx. message length 0


Attached debug vpm signal for working and non working case. I reset the calling num in debug to 01111111111






 Any one can help why the


Any one can help why the calling number sometimes display and sometimes no ?


I tried ring number 2 and 3 and 4 with no success


New Member

Seems like Telco is  not

Seems like Telco is  not sending you one.

[0/2/1] get_fxo_caller_id:Caller ID receive failed. 

Hi AJ, The incoming call is

Hi AJ,


The incoming call is through prima cell connected to the FXO port

prima cell is a name for the box that contain a mobile sim card


And yes I got Caller ID receive failed message when no calling number appear

But you think this box have a problem with sending the caller ID ?


I test it with analog phone and caller ID is working




New Member

  Hi Haitham Hadad, Have you



Hi Haitham Hadad,


Have you solved FXO caller id issue.


Please share it as I got the same issue.

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