The OTRS Daemon

OTRS Daemon Graphical Interface
OTRS Daemon Command Line Interface
Main Daemon Tools
Other Daemon Tools

The OTRS Daemon is an independent set of system processes that plan and execute tasks in background, either on a recurrent basis or triggered by events. OTRS Daemon is fundamental for the correct system operation.

In previous versions of OTRS (from 3.1 to 4) there was another process called OTRS Scheduler that does part of the work that the OTRS Demon do in OTRS 5. This old process is replaced by the OTRS Daemon which was re-written from the ground to make it more stable, scalable and robust than its predecessor.

The OTRS Daemon is capable to handle up to 10 tasks at the same time and it can work cooperatively with other OTRS Daemons on different frontend servers in a cluster environment.

When idle OTRS Daemon consist in five processes:

Note

The number of active processes depends on the number of tasks that the OTRS Daemon is executing simultaneously in a time frame.

By default the each daemon logs all error messages on a separated file located in /opt/otrs/var/log/Daemon/*.log. These logs are kept in the system for a defined period. To change this behavior and/or to also log the non error messages, please update SysConfig settings in Daemon -> Core::Log.

When a task could not be executed successfully for any reason, an email is sent to a predefined recipient reporting the issue. The content of the email includes the error messages and trace (if available).

The OTRS Daemon is an automated process that normally does not require human interaction. However it is possible to query its status and start or stop it if needed.

To be sure that the OTRS Daemon is running there is a Cron job that constantly checks that the process is alive. The main daemon is prepared to work even without a database connection, so is perfectly safe if the Cron task to start it is executed even before the database process in the system startup, and it is also tolerant to database disconnections.

If for any reason the OTRS Daemon needs to be stop (for example during a system maintenance), all unhandled tasks are saved, and as soon as the process is started again it continues with all pending tasks. For recurring tasks it will only execute the last instance of the task (if its due time was during the downtime).

OTRS Daemon Graphical Interface

The OTRS Daemon is not visible in the OTRS Graphical User Interface unless it stops running.

When the system detects that the OTRS Daemon is not running, a notification is presented to a defined group of users ("admin" by default).

To disable the notification (not recommended), change or add the notification groups, please edit the Frontend::NotifyModule###800-Daemon-Check setting in the SysConfig.

Figure 4.130. Daemon notification

Daemon notification


Clicking the notification the system presents an overlay window explaining the steps to bring the OTRS Daemon up and running.

Figure 4.131. Start Daemon

Start Daemon


OTRS Daemon Command Line Interface

The OTRS Daemon command line tools let you control the main daemon process (Start / Stop) or query its status. There are also tools to get more detailed information about the other four children daemons.

Main Daemon Tools

To start, stop or query daemon status bin/otrs.Daemon.pl script is used.

Example 4.30. Example to start the OTRS Daemon

shell> cd /opt/otrs/
shell> OTRS_HOME/bin/otrs.Daemon.pl start
                    


Available Options

  • start - to start the OTRS Daemon process.

  • stop - to stop the OTRS Daemon process.

  • status - to query the OTRS Damon process status.

  • start --debug - to start the OTRS Daemon process in debug mode.

    In this mode each daemon reports different messages depending on the actions that are been executed. This mode is not recommended for production environments.

  • stop --force - to stop the OTRS Daemon process in reducing the wait for children processes to finish.

    A forced stop reduces the amount of time the main daemon waits to successful stop the other children processes from 30 seconds (normal) to 5 seconds (forced).

Other Daemon Tools

To list all configured child daemons that the main daemon should start and keep running use the console command: Maint::Daemon::List.

Example 4.31. Example to list all configured daemons

shell> cd /opt/otrs/
shell> bin/otrs.Console.pl Maint::Daemon::List
                    


To list detailed information of all daemons use the console command: Maint::Daemon::Summary.

Example 4.32. Example to a summary of all daemon tasks

shell> cd /opt/otrs/
shell> bin/otrs.Console.pl Maint::Daemon::Summary