CDR Audio Recording File

I am a total noob to Asterisk and I know here is not FreePBX just Asterisk, however I really like the Asterisk platform and I am thinking of making commercial use to replace my old Siemens and Philips units. So I am studying, learning and testing Asterisk according to the premises I have for my project.

One of the main requirements of my solution is related to the audio recording of the entire call. This implies that I must record everything that the originator (outside the PBX) is listening to, and everything he says. However I found a problem on Asterisk that I don’t know how to solve.

I currently have this problem solved through the use of an FXO Gateway Server (basically a wiretapping) attacked directly on my link before entering my telephone exchange. This is an old, expensive and unreliable way.

Env Config

  • Use MixMonitor for Recordings - Yes
  • Call Recording Format - wav
  • Force Allow Conference Recording - Yes
  • Call Recording Policy - Caller
  • Inbound Routes - Call Recording to Force
  • Outbound Routes - Call Recording to Force
  • Applications → Call Recording - Call Recording Mode to Force, Destination Queue
  • The destination Queue -
  • Max Wait Time to Unlimited
  • Nobody added to queue
  • Join Announcement - Always
  • Music on Hold Class - inherit

Scenario
When the originator makes a call to the PBX, it is initially answered by the IVR, and then it is directed to a queue. When an agent is free to answer, then the call is routed to the agent.

Problem
I only have the audio recording after the agent answers the call. I don’t know what the calling side heard, and especially if he said anything while he was in line along the queue.

Question
I would like to know if you have any solutions to propose to record the call since it know PBX door, including announcements, hold music, etc.

Wht I have done so far
So, I made a call to the queue and I could see a .WAV file on file system related to my call as:
/var/spool/asterisk/monitor/2021/03/31/in-8000-51995482017-20210331-181023-1617225023.0.wav

So I downloaded the file to my local machine, and tried to listen to it. Media player could open the file, but it has no audio, zero seconds recorded, just an empty file.

But accordingly to the FreePBX documentation on:
https://wiki.freepbx.org/display/FPG/Call+Recording+Module+User+Guide

I should have a file within audio recorded as says:
“If a call is to be recorded, it can start immediately. This will incorporate any announcements, hold music, etc. prior to being answered.”

What I’m missing out?

Thank you,
Andrew Paes

Some of this is in FreePBX terminology, and, in particular, I don’t know where FreePBX inserts MixMonitor in relation to the call answer and the invocation of the Queue application.

However, are you sure the file has been closed. The meta data for the file won’t get updated until just before it is closed, so the file will be of non-trivial size, but appear empty to media players, up and till that point.

The nearest you will get to recording everything, with Asterisk, is to start the recording in original channel, but then invoke a local channel, with the no-optimise option, to do the actual work. There will still be some things that the caller hears that can’t be captured, as they are generated upstream of Astiersk.

Hi david, yes I’m sure the file was closed. I’m aware how MixMonitor works and answering earlier question, it was started as soon as calls arrive on PBX.

I didn’t try to open file before MixMonitor closes.

start the recording in original channel, but then invoke a local channel, with the no-optimise option, to do the actual work” - How can I set this up?

will still be some things that the caller hears that can’t be captured, as they are generated upstream of Astiersk.” - What kind of things?

Thanks man,

Ring back tone, is the obvious example.

https://wiki.asterisk.org/wiki/display/AST/Local+Channel+Optimization#LocalChannelOptimization-DisablingLocalChannelOptimization