Gatekeeper allows administrators to take a WordPress site offline quickly and easily while leaving it fully accessible to administrators and other authorized users. Site visitors will be shown or redirected to a specified offline page. An optional blacklist can be used for permanent bans.
** Features **
Visitors can either be redirected to an existing non-WordPress offline page (using http 302 temporary redirect) or WordPress pages can be temporarily replaced with the offline page.
Logged in admins can be whitelisted
The current admin’s IP address can be automatically whitelisted
An IP-based whitelist that can accept specific IP addresses, wildcards, and ranges
A basic IP-based blacklist that redirects blacklisted IPs to a specified page (not to be used for security)
A notifier that appears on administrator pages when the site is offline