supervisord

Configuring Supervisord

WARNING: This is an advanced topic. Overlord ships with safe defaults that work in most environments, so you don't need to configure the following unless strictly necessary.

The supervisord configuration that is sent with Overlord can be configured in some parts not to get information that is considered "extra" or basically not to get information that we don't want. An example is the poll-jail-extras:

[program:overlord-poll-jail-extras]
command=/usr/local/bin/overlord poll-jail-extras
autorestart=false
redirect_stderr=true
stdout_logfile=/var/log/overlord/%(program_name)s.log
environment=OVERLORD_CONFIG=/usr/local/etc/overlord.yml,PATH="%(ENV_PATH)s:/usr/local/bin",HOME=/root,USER=root

You can disable it completely (just comment it out). Of course, restart supervisord using service supervisord restart for the changes to take effect.

This means that the API will show the user empty information, so think if this is ok, maybe reducing the information to collect is a better idea, so read Configuring Overlord.

The poll-jail-extras command has a useful parameter called --item to poll for jail-specific information. In my system I use that parameter to collect only the parts of the healthcheckers, needed for AutoScaling.

[program:overlord-poll-jail-extras-healthcheckers]
command=/usr/local/bin/overlord poll-jail-extras --item healthcheck
autorestart=false
redirect_stderr=true
stdout_logfile=/var/log/overlord/%(program_name)s.log
environment=OVERLORD_CONFIG=/usr/local/etc/overlord.yml,PATH="%(ENV_PATH)s:/usr/local/bin",HOME=/root,USER=root

However, you can use the --item parameter multiple times, which is useful to further separate the processes achieving better results when the CPU has multiple cores.