metrics.prefix configures the template for the prefix of all reported metrics.

Each metric has a unique name which is hard-coded to

The value is expanded by the text/template package and provides the following variables:

  • Hostname: the Hostname of the server
  • Exec: the executable name of application

The following additional functions are defined:

  • clean: lowercase value and replace . and : with _

Template may include regular string parts to customize final prefix


Server hostname: Binary executable name: fabio

The template variables are:

.Hostname =
.Exec = fabio

which results to the following prefix string when using the default template:


The default is

metrics.prefix = {{clean .Hostname}}.{{clean .Exec}}