Installing Red Hat Enterprise Linux
Foreword
There’s a difference between knowing the path and walking the path.
– Morpheus
Linux is a free and open-source operating system based on the Unix operating system. It is highly customizable and has a wide range of software available for it. It is present on a vast range of devices, from supercomputers to appliances and up to tiny IoT sensors. Linux is known for its stability, security, and performance, and thus used by millions of people worldwide. The greatest asset Linux has is its user community. In my opinion, it is worth spending some time learning Linux as it will repay you multiple times across wide range of professions.
Red Hat Enterprise Linux (RHEL) is a popular operating system widely used by businesses and organizations for mission-critical applications and services. RHEL is based on the Linux kernel and is known for its stability, reliability, and security features. It comes with tools and features designed to help organizations manage their IT infrastructure. RHEL is also known for its strong support and enterprise-level technical support services. With recent policy changes in the Red Hat Developer Program, RHEL became great choice for individual developers and small shops. For these reasons, I have selected this distribution as a role model for this article.
Red Hat Content Delivery Network
Red Hat Content Delivery Network (CDN) is a scalable global distribution platform that hosts various software packages such as OS installation images and application files, including regular feature updates and security patches. Published packages are reviewed and signed which provides additional trust and increases overall security and integrity.
To access these resources you need to be authenticated. This is accomplished by attaching a subscription through a system registration process managed by Red Hat Subscription Management.
One of the ways how to acquire a valid subscription is to take advantage of Red Hat Developer Program.
Red Hat Developer Program
Red Hat Developer Program is a community-driven program that provides developers access to a wide range of resources. One of the highlights that applies to our context is that it also allows individuals to register for up to 16 systems (physical or virtual) for personal use which is ideal for labs, proof-of-concepts, and small production environments without any associated cost.
The developer subscription is valid for one year, afterwards, you need to perform registration again, which is simple in practical terms means you need to agree to ToC from a license point of view and re-register systems that consumed subscriptions from the previous year.
Now that we laid out the foundation let’s register for a developer account. For that, navigate to https://developers.redhat.com/register. Fill out and submit the registration form as illustrated below.
Once you verified your email address and set the cookie preference you can log in at https://developers.redhat.com/login.
After you log in, navigate to subscription management at https://access.redhat.com/management. When accessed for the first time, you are required to complete your profile by selecting the account type. Make sure you chosen Personal. Finally, fill out some additional mandatory information about yourself and hit Submit button.
Afterwards, you will be welcomed by the main subscription management screen. Here you see a breakdown of available subscriptions, manage systems, and further bugfix, enhancement, and security advisories that affect your registered systems.
Red Hat Subscription Management
As described previously, the subscription management portal can be accessed at https://access.redhat.com/management.
There are multiple ways how you can organize your subscriptions, including using the Simple content access which is active by default or by creating Activation Keys. However, to keep it simple, the only information for registering a system after OS installation is the username and password used to access this portal.
💡Tip: You can also interact with Subscription Management service using REST API.
OS installation
Installation media
For Red Hat Enterprise Linux there are multiple installation images available at Product Downloads. The main difference between the Binary DVD and Boot ISO images is that the Binary DVD includes additional packages and is ideal for environments without access to Internet during installation time, therefore is bigger in size. Finally, the KVM Guest Image can be used to create virtual machine on a KVM/QEMU hypervisor.
These are all standard installation media provided by Red Hat. If you need to create a custom installation you can leverage the Image Builder tool.
Standard Installation
Objectives
Greetings, it is your first day at your new gig, where you joined as an infrastructure consultant. Your objective, shall you accept, is to install Red Hat Enterprise Linux OS on a server that will act as a test KVM/QEMU hypervisor for the PoC environment. You received a laptop with a corporate image of Windows with Hyper-V at your disposal, which you can use as your test bed before installing it on bare metal.
The Virtual Machine specifications are as follows:
| Settings | Value |
| -------------------- | --------------------------------- |
| Name | rhel01 |
| Generation | Generation 2 |
| Firmware | EUFI |
| Secure Boot | Enabled |
| Secure Boot Template | MicrosoftEUFICertificateAuthority |
| Processor | 2 |
| Memory | 4 GB |
| Network Adapter | Default Switch |
| Virtual Hard Disk | VHDX |
| Virtual Disk Size | 50 GB |
| DVD Drive | ISO Image |The OS specifications are as follows:
| Settings | Value |
| ------------------- | ------------------------- |
| Languange | English (US) |
| Hostname | rhel01.example.com |
| Timezone | America/New_York |
| Storage | Automatic partitionioning |
| Network | DHCP |
| Root Password | D0ntUs3m3! |
| User Name | ansible |
| User Password | L3tm3HelpYou! |
| User Group | wheel |
| Base Environment | Server with GUI |
| Installation Source | rhel-9.2-x86_64-dvd.iso |If a setting is not included in above table assume default installer selection. The registration process will be performed using subscription-manager after the OS installation finished.
Good luck.
Solution
In this solution, we will use the Red Hat Enterprise Linux 9.2 Binary DVD as the source for installing Red Hat Enterprise Linux as a virtual machine.
Since we are not focusing on Hyper-V specific VM deployment details, I have prepared a sample PowerShell script that automates the creation of a VM that will meet the VM specifications defined in the objectives.
# Download the script
> Invoke-WebRequest -Uri "https://raw.githubusercontent.com/maroskukan/hypervisor-cookbook/main/hyperv/scripts/vm_create.ps1" `
-OutFile "vm_create.ps1"
# Execute the script, update isoPath according your environment
> .\vm_create.ps1 -Name rhel01 `
-Size S `
-IsoPath D:\iso\rhel-9.2-x86_64-dvd.isoAfter the virtual machine creation, a VM console will open. The installation media’s GRUB2 bootloader menu is displayed.
💡Tip: You may notice that the Hyper-V VM console does not support access to hosts clipboard, however it is possible to carry out the graphical installation remotely using VNC protocol which supports this feature. In order to start VNC server in the installation environment, select the Troubleshooting menu entry and then Install Red Hat Enterprise Linux 9.2 in text mode. Once in there you will have an option to Start VNC server and optionally set the password.
Select the Install Red Hat Enterprise Linux 9.2 menu entry and hit Enter. This will start the Anaconda Graphical installer.
💡Tip: Graphical installer is presented on TTY6 by default. The shell is available at TTY2by hitting CTRL + ALT + F2. Explore other terminals by hitting CTRL + ALT + Fx where x is the terminal number between 1 and 6. You can also use CTRL + TABto switch between TTYs. A careful eye may notice that these ware briefly described when the installer starts at the bottom of the screen as:
[anaconda]:main* 2:shell 3:log 4:storage-log 5:program-logOnce the installer loads, the Welcome screen is presented. We have the option to select the language.
On the Installation Summary screen, we select the Installation Destination under the System category.
We ensure that the one available local disk is selected and click Done.
On the Installation Source we ensure that device sr0 is automatically selected.
On the Software Selection screen we ensure that Server with GUI is selected.
On Network & Host Name screen, we update the hostname to rhel01.example.com and also ensure that we receive IP configuration from DHCP.
On the Root Password screen, we set the password and make sure that account is not locked.
On Create User screen, we create an additional user and ensure that he is part of the wheel group by checking the Make this user administrator option.
Finally, we begin the installation.
Once installation completes, we will reboot the system.
When the reboot completes, we log in as the user we created during installation.
On the Gnome Activities screen, we open the Gnome Terminal to register the system and update all installed software packages. You need to provide your Red Hat credentials created in the previous section.
# Register the system with subscription manager
$ sudo subscription-manager register
# Update the installed packages
$ sudo dnf update -yWe can verify that related Hyper-V modules and services are installed and running and that the CPU virtual extensions required for running KVM/QEMU hypervisor are available to the OS.
# List Hyper-V related modules
$ lsmod | grep hv_utils
hv_utils 57344 3
hv_vmbus 155648 7 hv_balloon,hv_utils,hv_netvsc,hid_hyperv,hv_storvsc,hyperv_keyboard,hyperv_drm# List Hyper-V related services
$ systemctl list-units --type=service | grep Hyper-V
hypervfcopyd.service loaded active running Hyper-V FCOPY daemon
hypervkvpd.service loaded active running Hyper-V KVP daemon
hypervvssd.service loaded active running Hyper-V VSS daemon
# Validate the support Intel VT-x or AMD-V virtualization technology
$ grep -E 'vmx|svm' /proc/cpuinfoFinally, we close the Gnome terminal and return to main desktop.
📝Note: If you don’t need this Virtual Machine anymore, you can decommission it using the following PowerShell script. It will remove the VM and delete any associated leftover files. Afterwards, also you need to remove the system in Subscription management portal or through REST API as demonstrated below.
# From Hyper-V host, download the script
Invoke-WebRequest -Uri "https://raw.githubusercontent.com/maroskukan/hypervisor-cookbook/main/hyperv/scripts/vm_delete.ps1" `
-OutFile "vm_delete.ps1"
# Execute the script
.\vm_delete.ps1 -Name rhel01# Enter Offline Token from https://access.redhat.com/management/api
$api_endpoint = "https://api.access.redhat.com/management/v1"
$auth_endpoint = "https://sso.redhat.com/auth/realms/redhat-external/protocol/openid-connect/token"
$offline_token = Read-Host -Prompt "Enter offline token"
$system_name = "rhe01"
# Generate access token
$body = @{
grant_type = "refresh_token"
client_id = "rhsm-api"
refresh_token = $offline_token
}
$access_token = (Invoke-RestMethod -Uri $auth_endpoint -Method POST -Body $body).access_token
# Retrieve System href for rhe01
$href = (Invoke-RestMethod -Uri "${endpoint}/systems/?limit=1&filter=${system_name}" -Headers @{ Authorization = "Bearer $access_token" }).body.href
# Remove System based on href
Invoke-RestMethod -Uri $href -Method DELETE -Headers @{ Authorization = "Bearer $access_token" }Congratulations, you have completed all listed objectives. On top of that, you updated the system and validated that Hyper-V guest tools are working and that support for KVM/QEMU on this VM is enabled.
Closing thoughts
I hope you had as much fun reading this article as I had writing it. If you are hungry for more articles like this one, let me know in the comments section below.
