In my years as a system administrator, I learned that security is much more complex than most people realize. You cannot get away with doing just one thing. One security measure will not save your dedicated server or VPS. Your security must be comprehensive and constantly adapting to defend against intruders. The following are three lessons I have learned over the years.
1. A firewall is not enough – This is the perfect example of a single security measure that will not get the job done. Firewalls protect your internal network and may save you from the most basic forms of attack, but cyber criminals are always thinking of new ways to get in and do damage. A firewall cannot protect you from OS and application vulnerabilities anymore than a bullet-proof vest will protect you from a cold.
2. Attackers love the /tmp directory – Lock this directory down. It will save you from endless headaches and grief. Attackers love to exploit weaknesses in your system and then drop their scripts into /tmp where they can do more damage or attack other servers.
3. A server hack can go unnoticed – We often assume that any attack on a server will bring it to its knees or at least send up a red flag. In reality, most are subtle, and a hacker may use your server to do something inconspicuous like running an unauthorized chat server. You must be proactive to catch them when they first make their attempt.
There are more lessons, not all related to security, that I will share over time on this blog. Hopefully, they will help those new to dedicated servers save time and money.