Monitor()

Since N/A Applications

Monitor a channel.

Last reviewed 2026-03-07

Monitor(file_format:[urlbase],[fname_base,[options]]])

Dialplan Builder -- build your Monitor() command

file_format

fname_base (optional)

Base filename (optional)

options

m: Mix both legs into one file when done

b: Only record when bridged

B: Play periodic beep

i: Skip recording input stream

o: Skip recording output stream

Full arguments reference

file_format
- file_format required - Optional. If not set, defaults to 'wav'
- urlbase
fname_base - If set, changes the filename used to the one specified.
options
- m - When the recording ends mix the two leg files into one and delete the two leg files. If the variable MONITOR_EXEC is set, the application referenced in it will be executed instead of soxmix/sox and the raw leg files will NOT be deleted automatically. soxmix/sox or MONITOR_EXEC is handed 3 arguments, the two leg files and a target mixed file name which is the same as the leg file names only without the in/out designator.
  If MONITOR_EXEC_ARGS is set, the contents will be passed on as additional arguments to MONITOR_EXEC. Both MONITOR_EXEC and the Mix flag can be set from the administrator interface.
- b - Don't begin recording unless a call is bridged to another channel.
- B(interval) - Play a periodic beep while this call is being recorded.
  - interval - Interval, in seconds. Default is 15.
- i - Skip recording of input stream (disables 'm' option).
- o - Skip recording of output stream (disables 'm' option).

Description

Used to start monitoring a channel. The channel's input and output voice packets are logged to files until the channel hangs up or monitoring is stopped by the StopMonitor application.

By default, files are stored to /var/spool/asterisk/monitor/. Returns '-1' if monitor files can't be opened or if the channel is already monitored, otherwise '0'.

Arguments

file_format
- file_format required - Optional. If not set, defaults to 'wav'
- urlbase
fname_base - If set, changes the filename used to the one specified.
options
- m - When the recording ends mix the two leg files into one and delete the two leg files. If the variable MONITOR_EXEC is set, the application referenced in it will be executed instead of soxmix/sox and the raw leg files will NOT be deleted automatically. soxmix/sox or MONITOR_EXEC is handed 3 arguments, the two leg files and a target mixed file name which is the same as the leg file names only without the in/out designator.
  If MONITOR_EXEC_ARGS is set, the contents will be passed on as additional arguments to MONITOR_EXEC. Both MONITOR_EXEC and the Mix flag can be set from the administrator interface.
- b - Don't begin recording unless a call is bridged to another channel.
- B(interval) - Play a periodic beep while this call is being recorded.
  - interval - Interval, in seconds. Default is 15.
- i - Skip recording of input stream (disables 'm' option).
- o - Skip recording of output stream (disables 'm' option).

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