A Brief Introduction
RedHat Enterprise Linux is a paid distribution of linux (which seems counterintuitive considering that linux is usually open source and free), due to the “enterprise” features that Red Hat offers its customers. As such, there are other flavours of linux that closely resemble RHEL, including CentOS and Fedora.
RHEL is run by the company RedHat, who provides support for enterprise customers. The primary focus of RHEL is stability. Enterprise customers often prefer to have 99.9% uptime on their servers, rather than a robust and complete feature set. Because of this, RedHat is able to charge commercial customers for the stability and customer support that is offered through their platform.
CentOS is directly based off of the commercial releases for RHEL, meaning that it is a perfect approximation of a RHEL server with different branding. Fedora however, is a distribution run by RedHat, and essentially acts as their less-stable pilot platform. Fedora has quick release cycles, and is community driven, making it free for everyone to use. Generally features that are developed for fedora and deemed to be stable are integrated in RHEL.
As such, installing CentOS is the recommended way to create a nearly-identical Red Hat linux experience, without having to pay anything for it.
RHEL Installation Requirements
The installation process for RHEL is fairly simple. In order to install RHEL or CentOS in a Virtual Machine you will need:
- A developer ISO of RHEL (free with a developer account) a. This can be substituted with a free CentOS ISO from https://www.centos.org/download/
- An installed copy of VirtualBox (https://www.virtualbox.org/wiki/Downloads) a. This can also be substituted for VMWare Workstation depending on personal preference.
Creating the VM
Here is how to install RHEL in a new VirtualBox VM:
- In the Virtual Box home page, click the “New” button to start the VM Creation wizard
Create a new Virtual Machine with a name, a default folder, and set the type to Linux (version Red Hat)
Set the memory allowances for the machine using the slider (Here i have set mine to 2048MB or 2GB)
Create a new virtual hard disk, with the type VDI (VirtualBox Disk Image)
- Set the size to Dynamically Allocated and continue
- Set a file location on your system to store the VDI, then allocate a maximum size (mine is set to 20GB)
- Click Create to create the new Virtual Disk, then Create again to create the virtual machine.
You should now have an empty Virtual Machine that looks like this:
Adding the Installation Media
Now we can pass the machine the installation media we downloaded earlier.
- Select the new VM that was just created, and click Settings
- Navigate to the Storage tab
Under “Storage Devices” there will be two sections, “Controller: IDE” and “Controller: SATA”. The SATA controller refers to the VDI that was created earlier. Controller IDE is what points to our installation ISO.
- Create a new disk in the controller IDE section (click the CD with a + symbol)
- Once the new window opens, click the “ADD” button (CD with + again) and select the ISO you downloaded earlier
Now it will appear as “attached” in the menu
- Select the ISO and click “choose”
This new ISO should now appear under “Controller IDE” in the storage menu
- You can now click OK to exit the settings menu
- With the VM still selected, click “Start” to boot up the VM into the installation ISO