System information
Dialplan Applications
The CEL system includes a single dialplan application that lives in the app_celgenu-
serevent.so module. This application is used to generate custom user-defined events of
the type EV_USER_EVENT. A practical example of using this would be for logging a caller’s
choices in a menu:
exten => 7,1,CELGenUserEvent(MENU_CHOICE,Caller chose option 7)
For full current details on the syntax of the CELGenUserEvent() application, use the built-
in documentation from the Asterisk CLI:
*CLI> core show application CELGenUserEvent
cel.conf
The CEL system has a single configuration file, /etc/asterisk/cel.conf. All options set here
affect CEL processing, regardless of which logging backend modules are in use.
Table 24-10 shows the options that exist in this file. All options should be set in the
[general] section of the configuration file.
Table 24-10. cel.conf [general] section options
Option Value/Example Notes
enable yes Enables/disables CEL. The default is no.
apps dial,queue Sets which dialplan applications to track. The default is to track no applications.
EV_APP_START and EV_APP_END events will be generated when channels
start and stop executing any tracked application.
events CHAN_START,CHAN_END,
ANSWER,HANGUP
Lists which events to generate. This is useful if you are only interested in a
subset of the events generated by CEL. If you would like to see all events, set
this option to ALL. The default value is to generate no events.
datefor
mat
%F %T Specifies the format for the date when a CEL event includes a timestamp. For
syntax information, see the manpage for strftime by running man
strftime at the command line. The default format for the CEL timestamp is
seconds.microseconds since the epoch.
At a minimum, to start using CEL, you must set the enable and events
options in /etc/asterisk/cel.conf.
Backends
As with the CDR system, there are a number of backend modules available for logging
CEL events. In fact, all of the CEL backend modules were derived from CDR modules,
so their configuration is very similar. In addition to the configuration options for
540 | Chapter 24: System Monitoring and Logging