Configuration Files

Rancher Configuration Files and Environment Variables

Rancher uses a number of configuration files:

• rancher.cfg
• conf/defaults.toml
• conf/supported.toml
• conf.d/builds.toml
• conf.d/build_lists.toml

The rancher.cfg file has all of the global rancher settings, like the location of the .toml files, logging settings, etc. All settings within this file can be overridden using environment variables; including the location of the rancher.cfg file. Rancher will first check to see if the environment variable is set. If it is empty, rancher will use rancher.cfg's setting, except for rancher.cfg which, by default is in the same directory as rancher.

The merging, or overriding, of the settings within defaults.toml and supported.toml result in the default configuration for a given distro, including the default iso image to use. The default configuration for the distro should result in a fully usable and properly, if minimally, configured artifact mostly following Vagrant conventions. As such, these files are not intended to be modified. Ideally, all modifications to the default configurations are done in builds.toml. If the same changes are consistently needed within build configurations, modifying the defaults.toml and supported.toml is probably the best way to ensure consistency with minimal additional modifications.