# Maintenance

A Wolff project can enter into maintenance mode quite easily.

The constant maintenance_on defined in the config.php file indicates if the project is under maintenance or not, just change its value to true if you want to activate it.

When under maintenance, a default _maintenance.php controller will be called if the client IP address isn't in the white list.

White list

A white list file is the one that defines which IP address will still have access to the page content when it's under maintenance.

It should be located under the system/definitions directory and should be named maintenance_whitelist.txt.

You can create it in a fast way calling the createFile method:

Maintenance::createFile();

Add IP

Adding an IP address to the white list:

Maintenance::addAllowedIP('127.0.0.1');

If the white list file doesn't exists, it will be created automatically.

Delete IP

Deleting an IP address from the white list:

Maintenance::removeAllowedIP('127.0.0.1');

Get IP list

Get all the IP address in the white list:

Maintenance::getAllowedIPs();

This will return the IP list as an array.

Client Allowed

You can know if the current client IP address is in the white list with the following method:

Maintenance::isClientAllowed();

Remember that you can add and remove IPs using the CLI of Wolff too.