The Linux and OS X versions of ESET NOD32 Anti-Virus (Business Edition) require an X-server to present in order to install. Since this isn’t an issue on OS X, it might on Linux since this isn’t installed on most servers. Although you can use the ESET Remote Administration Console to generate a custom installer to circumvent this, sometimes you might need to make a manual change in the configuration. I will show you how to do this using the command line (very useful for remote access).
A very useful application for Linux and BSD systems is the sudo application. This allows a user to execute a root task without being logged in as root. There are some security concerns when this is not configured correctly. Fortunately most distributions have this enabled only for the ‘sudo’ usergroup. But in some cases you want sudo to merge into your environment, instead of having to change your environment for sudo.
Since PHP version 5 has been released, it has been improved with Object-Oriented Programming, using classes. It’s one of the most used features in system programming languages like C++ and can now be used in PHP.
In this article I assume you know the following in advance:
– You know what variables are and how to assign values to them in PHP.
– You know what a function is and how it works.
Before I start, I want to tell a bit about functions.
Using SSH is a great way to remotely manage a server and to securely transfer data to and from it. You basically connect using SSH with your username and password. In that case you authenticate with something you know, which in this case is the password.
But you can also authenticate with something you have, like an SSH key. You can use this to authenticate without a password, and even configure the server to only allow SSH keys to prevent password attacks.
This tutorial shows how to configure the SSH server, generate SSH keys for each user and optionally disable password logins.
Many people who are configuring a web server for the first time are struggling with the proper file and group permissions. Either the scripts don’t execute properly, or they can’t upload or modify files without getting a Permission Denied error message. The only way to make it work is by setting the CHMOD permissions to 777 (world read, write and execute), which is very dangerous. Any individual could upload a (PHP) script to the server, and cause serious damage (erase the files or even disrupt the OS if the security is very weak). I’m going to teach you how to set up the permissions properly to make the server both functional and safe.
During the creation of PHP scripts you might encounter a situation where a value needs to be passed from one page to another. This will mostly be required when sending the visitor through a wizard or a login screen. This can be achieved by using:
- HTTP GET
- HTTP POST
I will briefly explain each of those.