java.net.NoRouteToHostException: No route to host error is one of a few known errors that appear when you’ve been infected with malware through one of the plugins you’ve installed on your Bukkit based server. You’ll normally find infected plugins on sites that leak premium plugins or re-host them away from the authors official source, though the official source can be compromised on rare occasions.
If you’re receiving this error you’ll need to take immediate action by following the steps below.
- Stop your server and take a manual backup using our Manual Backup guide.
- Delete and re-install all of the plugins currently on your server
- You’ll want to make sure you take note of the plugins you currently have, your backup can help with that.
- Make sure you delete all of them. The malware can spread between plugins and missing one can cause it to spread again.
- Make sure to download them from the official sources. Do not download any plugins from a site that re-hosts plugins or hosts plugins that - are otherwise sold by their author. Good sources include but are not limited to
- Delete and re-install your server software.
- Take a “clean” backup before starting your server.
- Start your server and take another backup and run MCAntiMalware.
5.1. You’ll need to start your server, stop it, and take another backup.
5.2. You’ll want to run MCAntiMalware to make sure that you weren’t infected again.
- You can run MCAntiMalware by changing the Server Jar option in your servers Startup Parameters to the name of the jar you download from the MCAntiMalware page.
6.1 If you were infected, revert back to your “clean” backup and run MCAntiMalware before starting your server to get a list of what plugins are infected before the server starts. If you downloaded them from the official sources, you may need to contact those plugin authors.