ForceIP was designed for servers where the IP(Domain) was just recently changed. If the user attempts to connect with an IP not listed, it will disconnect them with a configured message. This works way better than putting signs up around spawn which nobody reads. This forces them to do it to play. This also works great for Bungee servers where the player is attempting to login using backend IP's. It disallows that.

forceip.bypass : Allows a user to connect even when not using a set IP.

• IPS : A list of IPs that are allowed to connect with. This plugin uses "include", so if you want them to join on any subdomain within a domain, just enter the domain.
• message: The message they get when they are disconnected. You may use color codes, and "\n" for a new line.
• debug: If a player can't connect, it will tell the console which IP they are using.
  
  

  BEFORE POSTING

If there is a bug in the plugin, the chances are, I already know about it. Please use the yellow "Download Latest Dev Build" button, and try that version first. They will most likely have the bug fixed. IF NOT, please make sure you meet the requirements(above). If all else fails, THEN you may post a comment below. PLEASE include the following in your comment:

• Bukkit/Spigot Version(/ver)
• ForceIP Version (/ver ForceIP)
• ERROR from console. Please use Pastebin to post the error.