RHEL 8

Installing Red Hat Enterprise Linux 8

Red Hat Enterprise Linux (RHEL) is a Linux Operating System developed by Red Hat. RHEL is generally aimed at the commercial market. Red Hat Enterprise Linux is available for multiple platforms including x86, x86_64, PowerPC, IBM pSeries and IBM System z (Mainframe). RHEL 8 is the latest available version from Red Hat (first released May 2019). If you wish to try RHEL 8, you can download an evaluation copy giving you a full 30 day free trial (including updates). The following Red Hat Installation guide can be used for installing a Red Hat 8 Minimal Server configuration with a custom disk and Static IP addressing scheme. To register and download your evaluation copy of Red Hat Enterprise Linux, simply follow this Link::

Download RHEL

Once you have downloaded your chosen image of RHEL 8 that matches your architecture, you will need to burn this to a blank DVD or if you are using a Virtual System, place the "iso" image in the relevant location that can be accessed by your Virtual System. Once you have burned your "iso" image of RHEL 8 to your DVD, you will need to leave the DVD in the DVD drive and reboot your system. (Assuming that this machine is your intended target system for installation). As your computer reboots, you will need to press the appropriate key to access your system's BIOS settings. On many systems this key will be "F8", "F11" or "F12". Most systems will display a message indicating which key needs to be pressed. Once you have access to your BIOS settings, you will need to modify the boot sequence order of your system to boot from CD/DVD first. Once you have made this change, you can reboot your system and follow the instructions below. If you are installing into a Virtual environment, simply copy the downloaded "iso" image to the relevant folder/data store.

RHEL 8 Installer

To start your installation of RHEL 8, highlight the "Install Red Hat Enterprise Linux 8" option and press enter. Your installation will now start.

Testing the media

I would always recommended that you test your media before carrying out an installation for the first time. If you wish to test your media, choose the option "Test this media and install Centos Linux 8". After a media check, your installation will start automatically.

Welcome to Red Hat Enterprise Linux 8

At this screen you will need to choose the language that you would like to use during your installation. In this example, "English", "English (United Kingdom)" has been selected. Once you have made your selection, click on continue in the lower right hand corner of the screen.

Installation Summary

At this screen various configuration options are available. Any option that is highlighted must be addressed before you can continue with your installation. It is from this screen that you can configure your Localization settings, Security Policy, Software and System settings.

Keyboard Layout

Your keyboard settings may be configured from this screen. Additional keyboard layouts may be added if required. If you have added additional keyboard layouts, you can move your chosen layout to the top of the list to make this the new default layout. The layout configuration may be tested by typing into the text box in the upper right hand corner. To add/delete or move layouts, simply use the relevant arrow keys in the lower left hand corner of the screen. Once you have made any changes, click on the "Done" button in the upper left hand corner of the screen.

Installation Source

If you have booted from the standard "iso" image of CentOS 8, then no further action is required at this screen. Click on "Done" to continue with your installation.

Software Selection

At this screen you can choose which "Base Environment" is to be used for your installation. Several server configurations are available. You should choose the option that best matches your requirements. In this example, "Minimal Install" has been selected. Any additional "Add-Ons" that are available may be selected from the right hand options panel. In this example, "Standard" has been selected. Click "Done" to continue with your installation.

Language Support

At this screen you need to verify or choose your Language settings. In the example, "English", "English (United Kingdom)" has been chosen. Click "Done" to continue.

Kdump

"Kdump" is a mechanism that will allow in the event of a system crash information to be collected for determining the cause of the crash. In this example, I have chosen to "Disable" kdump. To disable "kdump", un-check the "Enable Kdump" option. Now click "Done" to continue with your installation.

Configuring a Hostname

At this screen you need to enter a "hostname" to be used for your server. Type the hostname into the box located in the lower left hand corner of the screen. Once entered, click on "Apply". In this example, I have entered the hostname as "rhel08a".

Network - Using DHCP

If you are connected to your local network you may be able to obtain an IP address through DHCP (Dynamic Host Control Protocol). This is where you are given a leased (non permanent) IP address. You may want to consider configuring a static IP address (permanent). This is generally the normal practice used when configuring a server. To obtain a DHCP IP address, simply click on the "ON/OFF button.

Configuring a Static IP address

To configure a static IP address, click on the option "Configure".Next, you should see a "Pop-Up" menu where we are going to add our IP address, Netmask, Gateway and DNS server information. In the following example I will be using the following Network Addressing Scheme:

IP Address = 192.168.0.212
Netmask = 255.255.255.0
Gateway = 192.168.0.1
DNS Server = 8.8.8.8

You will need to enter your own details here. (Modify where applicable)

From the "Tabs" across the top of the menu, select "IPv4 Settings"

From the "Method" pull down menu, select "Manual"

Now click in the Address, Netmask and Gateway boxes and enter your settings.

Finally, give the name of your DNS Server (IP Address)

If your server is part of a domain, you can specify the order of which Domains should be searched first.

Once all settings have been entered, click "Save" to continue.

Date and Time

From this screen you need to choose your geographic location from either the map or from the pull down menu. In this example "Europe" and "London" have been selected. You can adjust the time and date by clicking on the relevant arrows in the lower left and lower right hand corners of the screen. You may also configure your system to use "NTP" for time synchronisation by clicking on the small gear icon in the upper right corner. (see step below)

NTP

If you have chosen to use a NTP server for time synchronisation, then you will need to add the address/name of the server you wish to use. Before this step can be configured, you will need to configure your Network Settings first!

Security Policy

From this screen you can select a policy that matches your needs. Various options may be available or the entry can be left blank. Click "Done" to continue.

Connect to Red Hat

Before you can download any updates and patches, you will need to register your server with Red Hat. you can either fill in your account details here, or use the "subscription-manager" method after the server has been built. My preferred method is to register the server after the build. How to do this will be covered at the end of the guide.

Root Password

You must specify a root password to be used for the administration of your system. Note, if you supply a weak password, you will be asked to press "Done" twice to confirm you have chosen a weak password! The strength of your password is also indicated.

Create User

From this screen you must define the name of a user. In this example I have also chosen the user to be an "Administrator". Again, if you supply a weak password, you will be asked to confirm this. Once you have supplied the relevant credentials, simply click "Done" to continue with the installation. It is strongly recommended that you use the "default" option of "Require a password to use this account".

Installation Destination

This screen allows you to configure your disk partitioning layout. Two options are available. "Automatically configure partitioning" and "I will configure partitioning". For this installation of RHEL 8, I am going to choose the option of manually configuring the disk partition layout "I will configure partitioning". For this installation of RHEL 8, I am going to create the following partition scheme using Logical Volume Management: Volume Groups (VG), Logical Volumes (LV) size of partition/file system in MB. You may wish to size your partitions/file systems differently to match your requirements. Note, as a rule of thumb, the swap size should be half the size of the physical memory. In this example I have set the swap size to be 1000MB as this CentOS system has 2GB of physical memory. The size of the disk used in this exercise has a capacity of 20GB.

Once you have selected the option "Custom", click on the "Done" button in the upper left hand corner of the screen.

Manual Partitioning

At this screen we can see that we have a "20GB" disk available to create our partitions/file systems. Available space is indicated in the lower left of the screen. To start creating our partitions and file systems, we will need to click on the "+" plus button in the lower left hand corner of the screen.

Add a New Mount Point

Each time you click on the click on the "+" plus button in the lower left hand corner of the screen, you will be presented with a small pop up menu. It is from this menu that you can select the "Mount Point" or enter the name of a mount point to create. You also need to specify the "Desired Capacity" to be used with each mount point. Values can be added as "GB" or "MB".

Create a Boot Partition

The first partition we are going to create is the boot partition. The "Mount Point" can be selected from the drop down menu and the desired capacity can by typed into the "Desired Capacity" box. Once the details have been entered, click on "Add Mount Point". Notice, the Device Type is set to "Standard Partition" for a boot partition. A size of 512MB was specified in this example.

Adding additional Filesystems

To add the remainder of our file systems, simply click on the "+" Plus button. Enter the appropriate values as per the table above. In this exercise we are going to change the default name of the Volume Group to be "sysVG". The last filesystem to be created will be "/spare".

The remainder of all file systems will have a Device Type of "LVM" a Volume Group of "sysVG". To change the name of the default Volume Group, click on the "Modify" button. A Volume Group configuration box will appear. Simply change the name from the default to "sysVG". The Logical Volume name is entered into the box "Name". For example, if you are creating the "/spare" filesystem, then the name "spareLV" will be used. At any time, you may press the "Update Settings button to apply any changes made.

You will notice that a filesystem called "/spare" is to be created. This file system is created last as we are going to assign all remaining space to this filesystem. To allocate the remaining space to this filesystem, simply leave the "Desired Capacity" value empty. The reason we allocate the remaining space to "/spare" is to allow us to easily allocate this space back to the Volume Group "sysVG". Once the system is built, we can remove this filesystem and all space will be then available to our system Volume Group "sysVG". This space can then be given to any of the file systems within the Volume Group "sysVG". Once you have configured all the file systems, you should end up with a layout similar to the one below. Once you are happy with your configuration, click on "Done" to continue.

Summary of Changes

A summary of changes will now be displayed. If you need to make any modifications, then select "Cancel and Return to Custom Partitioning". To continue, click on the "Accept Changes" button.

Begin Installation

Once all configuration settings have been entered, we are now ready to initiate the installation. This is done by clicking on the "Begin Installation" button in the lower right corner of the screen. Your system will now be installed. Progress is indicated by a progress bar in the centre of the screen.

Complete

Red Hat Enterprise Linux 8 has now been successfully installed. Your system needs to be re-booted before you can use it. Click on "Reboot" to finalise your installation. Remember to remove any media from your drives.

Login Screen

At this screen you can now login to your server with the accounts you created earlier.

Verify Filesystems

You can verify that the file systems that were created earlier have been mounted by issuing the command df -hT.

Registering your server

If you haven't already registered your server with Red Hat, you will need to do this now to be able to download patches and updates for your server.

The command to register your server is: "subscription-manager register". Once entered, fill in your account details to register your system. An example of registration is below.

[root@rhel08a ~]# subscription-manager register
Registering to: subscription.rhsm.redhat.com:443/subscription
Username: landoflinux
Password: 
The system has been registered with ID: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
The registered system name is: rhel08a
                           

List available subscriptions

To list available subscriptions you can issue the command: subscription-manager list --available

 
 [root@rhel08a ~]# subscription-manager list --available
+-------------------------------------------+
    Available Subscriptions
+-------------------------------------------+
Subscription Name:   30 Day Red Hat Enterprise Linux Server Self-Supported Evaluation
Provides:            Red Hat Beta
                     Oracle Java (for RHEL Server)
                     Red Hat Enterprise Linux Server
                     Red Hat CodeReady Linux Builder for x86_64
                     Red Hat Enterprise Linux for x86_64
                     Red Hat Ansible Engine
                     Red Hat Container Images Beta
                     Red Hat Enterprise Linux Atomic Host Beta
                     Red Hat Enterprise Linux Atomic Host
                     Red Hat Container Images
SKU:                 RH00065
Contract:            12345678
Pool ID:             xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Provides Management: No
Available:           2
Suggested:           1
Service Type:        L1-L3
Roles:               Red Hat Enterprise Linux Server
Service Level:       Self-Support
Usage:               Development/Test
Add-ons:             
Subscription Type:   Instance Based
Starts:              06/04/21
Ends:                06/05/21
Entitlement Type:    Physical

Subscription Name:   Red Hat Developer Subscription for Individuals
Provides:            dotNET on RHEL Beta (for RHEL Server)
                     Red Hat CodeReady Linux Builder for x86_64
                     Red Hat Enterprise Linux for SAP HANA for x86_64
                     Red Hat Ansible Engine
                     RHEL for SAP HANA - Update Services for SAP Solutions
                     Red Hat Enterprise Linux Scalable File System (for RHEL Server) - Extended Update Support
                     RHEL for SAP HANA - Extended Update Support
                     Red Hat Container Images Beta
                     Red Hat Ansible Automation Platform
                     Red Hat Enterprise Linux Atomic Host Beta
                     Red Hat Container Images
                     Red Hat Enterprise Linux Load Balancer (for RHEL Server)
                     Red Hat Container Development Kit
                     Red Hat Beta
                     Red Hat EUCJP Support (for RHEL Server) - Extended Update Support
                     RHEL for SAP (for IBM Power LE) - Update Services for SAP Solutions
                     Red Hat Enterprise Linux High Availability for x86_64
                     MRG Realtime
                     Red Hat Enterprise Linux Load Balancer (for RHEL Server) - Extended Update Support
                     dotNET on RHEL (for RHEL Server)
                     Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
                     Red Hat Enterprise Linux High Availability - Update Services for SAP Solutions
                     Red Hat Enterprise Linux Resilient Storage for x86_64 - Extended Update Support
                     Red Hat Enterprise Linux High Availability for x86_64 - Extended Update Support
                     Oracle Java (for RHEL Server)
                     Red Hat Enterprise Linux Resilient Storage for x86_64
                     Red Hat Enterprise Linux Server - Update Services for SAP Solutions
                     Red Hat Software Collections (for RHEL Server)
                     Red Hat Enterprise Linux for ARM 64
                     Red Hat Enterprise Linux High Performance Networking (for RHEL Server)
                     Red Hat Enterprise Linux Scalable File System (for RHEL Server)
                     Red Hat Enterprise Linux for Real Time
                     Red Hat Enterprise Linux High Performance Networking (for RHEL Server) - Extended Update Support
                     RHEL for SAP - Update Services for SAP Solutions
                     Oracle Java (for RHEL Server) - Extended Update Support
                     Red Hat Enterprise Linux Atomic Host
                     Red Hat CodeReady Linux Builder for ARM 64
                     Red Hat Developer Tools (for RHEL Server)
                     Red Hat Software Collections Beta (for RHEL Server)
                     Red Hat Enterprise Linux Server
                     Red Hat Enterprise Linux for SAP Applications for x86_64
                     Red Hat Developer Tools Beta (for RHEL Server)
                     Red Hat Enterprise Linux for x86_64
                     Red Hat Enterprise Linux for x86_64 - Extended Update Support
                     RHEL for SAP - Extended Update Support
                     Red Hat Developer Toolset (for RHEL Server)
                     Red Hat Enterprise Linux High Performance Networking (for RHEL Compute Node)
                     Red Hat S-JIS Support (for RHEL Server) - Extended Update Support
SKU:                 RH00798
Contract:            
Pool ID:             xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Provides Management: No
Available:           16
Suggested:           1
Service Type:        
Roles:               
Service Level:       Self-Support
Usage:               
Add-ons:             
Subscription Type:   Standard
Starts:              06/04/21
Ends:                06/04/22
Entitlement Type:    Physical
                           

Add a subscription

To add a subscription to our server we need to issue the following "subscription-manager" command along with the "Pool ID" that was obtained from the above output:

 
[root@rhel08a ~]# subscription-manager subscribe --pool xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Successfully attached a subscription for: Red Hat Developer Subscription for Individuals                            
                           

Verify Repositories

Now that you have activated your repositories, you can issue the "dnf repolist" command to confirm this.

 
[root@rhel08a ~]# dnf repolist
Updating Subscription Management repositories.
repo id                                             repo name
rhel-8-for-x86_64-appstream-rpms                    Red Hat Enterprise Linux 8 for x86_64 - AppStream (RPMs)
rhel-8-for-x86_64-baseos-rpms                       Red Hat Enterprise Linux 8 for x86_64 - BaseOS (RPMs)
                          

Checking for updates

Once your system has been register, you may now check for updates and install any available updates for your server. The command to check for updates is "dnf list updates" and the command to install the updates is "dnf update".