WordPress at a glance
action is not described

ms_network_not_found action-hook . WP 4.4.0

Fires when a network cannot be found based on the requested domain and path.

At the time of this action, the only recourse is to redirect somewhere and exit. If you want to declare a particular network, do so earlier.

Usage

add_action( 'ms_network_not_found', 'action_function_name_5459', 10, 2 );
function action_function_name_5459( $domain, $path ){
	// action...
}
$domain(string)
The domain used to search for a network.
$path(string)
The path used to search for a path.

Where the hook is called

ms_load_current_site_and_network()
wp-includes/ms-load.php 342
do_action( 'ms_network_not_found', $domain, $path );
wp-includes/ms-load.php 370
do_action( 'ms_network_not_found', $domain, $path );

Where the hook is used (in WP core)

Does not used.