There comes a time on every system administrator’s life when they need to start being a little more conscious about security. That time has finally come for me.
I have a couple of servers in DigitalOcean where I run various sites and services. Some of these need to communicate with each other to do their job, for example, this blog runs in a server with Apache and PHP and communicates with another server that is running a MySQL database.
This is all good, but one of the most important rules of security is to only allow access to resources on a per-need basis. What this means is that from a security standpoint, nobody should be able to access a resource unless explicitly allowed. This rule applies to almost all scenarios that require some kind of access control and is a good idea to follow it whenever possible.