*`action` (symbol) - The first argument that comes after either __before__ or __after__ when defining a new trigger (For example when the action is `:up` : `config.trigger.before :up`).
Can be any valid Vagrant command. It also accepts a special value `:all` which will make the trigger fire for every action. An action can be ignored with the `ignore` setting if desired.
*`ignore` (symbol, array) - Symbol or array of symbols corresponding to the action that a trigger should not fire on.
*`info` (string) - A message that will be printed at the beginning of a trigger.
*`on_error` (symbol) - Defines how the trigger should behave if it encounters an error. By default this will be `:halt`, but can be configured to ignore failures and continue on with `:continue`.
*`only_on` (string, regex, array) - Guest or guests to be ignored on the defined trigger. Values can be a string or regex that matches a guest name.
*`run_remote` (hash) - A collection of settings to run a inline or remote script with on the guest. These settings correspond to the [shell provosioner](/docs/provisioning/shell.html).
*`run` (hash) - A collection of settings to run a inline or remote script with on the host. These settings correspond to the [shell provosioner](/docs/provisioning/shell.html).
*`warn` (string) - A warning message that will be printed at the beginning of a trigger.