Although this may be difficult, the first thing to do is to remember not to panic. Staying calm will go a long way in making sure you can resolve the issue quickly and calmly. When operating a server remotely, your only assurance that a server is running is through its websites and through Internet connections.
1. The first thing to check is whether or not your own network connection is experiencing problems. Although you may be able to connect to some other sites, you may find that you cannot connect to certain sites.
2. If your connection is fine, check your web monitoring software or services, which should have notified you when there was a web connection problem.
3. If those indicate your server is down, check your data center or web host’s website for current network status. They may have already been aware of the problem and have posted some information about it.
4. Next, try connecting to your server via SSH. If you can get in through SSH, it means that a service, such as Apache or MySQL, may just need restarting.
5. If SSH is not accessible, your server may need a reboot. Follow the normal procedure to either automatically reboot or contact a support person to manually reboot your server.
6. In the rare case that even rebooting will not resolve the issue, some data centers will setup KVM remote console control so that you can fix whatever network issues your server is having. If you find it to be some type of problem with your operating system you cannot fix, they may have to re-image the machine and/or restore backups.
7. There are cases when something like KVM may turn up no visible issues. In such a case, the data center may need to fix a hardware or network problem. Be sure to have them investigate for any such issues.
Staying calm and running through a set lists of protocols should help you resolve your server downtime quickly and safely.