Reference

All configuration options can be specified either

• in the config file
• as environment variable
• as command line argument

and are evaluated in that order.

# fabio.properties
metrics.target = stdout

# correspondig env var (no prefix)
metrics_target=stdout ./fabio

# env var with FABIO_ prefix (>= 1.2)
FABIO_metrics_target=stdout ./fabio

# env var with FABIO_ prefix (case-insensitive) (>= 1.2)
FABIO_METRICS_TARGET=stdout ./fabio

# command line argument (>= 1.2)
./fabio -metrics.target stdout