The CentOS Linux distribution is a free version of the Red Hat Enterprise Linux distribution that is intended for datacenter deployments. This free operating system allows someone to setup a Linux server easily with a free and reliable operating system. CentOS comes with an older kernel version; 2.6.32.
[homer@neo ~]$ uname -a Linux neo.matrix 2.6.32-358.el6.i686 #1 SMP Thu Feb 21 21:50:49 UTC 2013 i686 i686 i386 GNU/Linux
This does not matter when you are using it. I am using an FTP server in this virtualized instance; so I have the FTP option ticked in the Firewall configuration to allow incoming connections. Then click reload and the settings will be applied. This will allow clients to connect to the FTP server. if you enable the SSH incoming connections in the firewall; then you may access the server remotely using an SSH client. Just type this command to get in.
ssh firstname.lastname@example.org -p 22
This will allow you to login to the machine and administer it over the network. The installation was not too painful; I installed it with an LVM partitioning scheme and the performance of the Gnome 2.32.2 desktop environment is very good in Virtualbox.
To enable sudo in CentOS where your username is homer:
homer ALL=(ALL) ALL
This line will enable the user homer to use the sudo command. This will prompt for the users password.
Use the yum update command to install all pending package updates. This will keep your system up to date.
If you are running CentOS in Virtualbox and you install the Guest Additions; just logout to the GDM login screen and back into Gnome and the desktop will resize to the full resolution. You do not need to restart CentOS for this to take effect.
This Linux distribution may be downloaded from the website: http://www.centos.org/.