Supervisor is a process control system used by the IzoT SDK to monitor and control the processes of an IzoT Server or IzoT application. It is configured by a set of *.conf files in the $IZOT/etc/supervisor directory.
Following is an example configuration file (this one is for the IzoT Server processes):
# IzoT Server Group [group:server] programs=network,api # IzoT Server - Network Server (LonBridge) prog = server:network [program:network] command="/home/debian/izot-sdk/bin/LonBridge" directory=/home/debian/izot-sdk/etc/lonbridge environment=LD_LIBRARY_PATH="/home/debian/izot-sdk/lib" user=debian priority=100 startsecs=30 autostart=false startretries=30 stdout_logfile=/home/debian/izot-sdk/etc/supervisor/server-network.log redirect_stderr=true # IzoT Server - REST API Server (via Gunicorn) prog = server:api [program:api] command="/home/debian/izot-sdk/bin/python3" "/home/debian/izot-sdk/izot/server/manage.py" run_gunicorn localhost:8000 directory=/home/debian/izot-sdk/izot/server environment=IZOT="/home/debian/izot-sdk",PYTHONPATH="/home/debian/izot-sdk" user=debian priority=200 startsecs=30 autostart=false startretries=30 stdout_logfile=/home/debian/izot-sdk/etc/supervisor/server-api.log redirect_stderr=true
where:
| Setting | Description |
|---|---|
| [group:groupname] | Names a group of programs to be controlled by Supervisor. |
| programs | A comma-separated list of programnames (see below) belonging to groupname. |
| [program:programname] | Defines a program to be controlled by Supervisor. |
| command | The command line that Supervisor will use to start the program. |
| directory | The directory that the program will be started in. |
| environment | A comma-separated list of environment variables that will be set in the program's process. |
| user | The user account under which the program will be started. |
| priority | Used to determine the order that Supervisor (auto-)starts the program relative to other auto-start programs. A lower value program will be started before a higher value program. |
| startsecs | The number of seconds that Supervisor will wait after starting a program before determining whether it started successfully. This time should be large enough for the program to initialize completely. |
| autostart | Whether Supervisor should automatically start the program when it starts (e.g. on initial power up or following a reboot). |
| startretries | The number of successive times Supervisor should attempt to start a program before giving up. |
| stdout_logfile | The path to a logfile that will receive the standard output from the program. Note that Supervisor-started programs do not run with an attached terminal so output is usually discarded. |
| redirect_stderr | Whether Supervisor should also redirect the standard error stream from program to the stdout_logfile. |
For further details on these and other settings, see the Supervisor Documentation.