Fedora CoreOS is an operating system minimum auto update to run containerized workloads safely and on a large scale. It is currently available for testing on a limited number of platforms.
The Fedora team introduced the new system operating as the successor to Fedora Atomic Host and CoreOS Container Linux. According to their explanationss, Fedora CoreOS is an operating system that combines the provisioning tools, the self-updating model and philosophy of Container Linux with Atomic packaging technology, OCI support, and SELinux security.
The Fedora team explains that although containers can be run on a full-size server operating system, an operating system designed specifically for containers can provide the functionality that a general operating system cannot.
As the required software is minimal and uniform, the entire operating system can be implemented as a unit with little customization. Therefore, Fedora CoreOS was designed to be now the safe and reliable host for your computing clusters.
Another rationale for Fedora CoreOS development is the fact that since containers are deployed across multiple nodes for redundancy, the operating system can automatically update and then restart without interrupting workloads.
About Fedora CoreOS
Basically Fedora CoreOS It has been specifically designed to run containerized workloads without regular maintenance.
It is also designed to update automatically with the latest operating system enhancements, bug fixes, and security updates. It comes with Ignition, runs containers with Podman and Moby, and updates automatically with rpm-ostree.
Whether you use the cloud, virtualization, etc., a Fedora CoreOS machine will always boot in one place - a generic image of the operating system.
Then, during the first boot, Fedora CoreOS will use Ignition to provision the system. Ignition reads an Ignition configuration from user data in the cloud or a remote URL.
Use these settings to create disk partitions and file systems, users, files, and systemd drives. The steps to provision a machine, if you decide to try the Fedora CoreOS preview, are explained by the team in the introductory ticket.
According to the team, Fedora CoreOS is designed to be managed as an immutable infrastructure. Once the machine is turned on, you should not modify or reconfigure it.
Instead, modify the FCC (Fedora CoreOS Settings) and use it to provision a replacement machine.
According to your explanations, this is very much like the way you manage a container. Container images are not updated, but are rebuilt from scratch and redeployed.
This approach makes it easy to scale as load increases. Just use the same power settings to start additional machines.
An important feature highlighted by the Fedora CoreOS team is automatic updates.
By default, the Fedora CoreOS operating system will automatically download the new available versions, install them atomically, and then restart them.
According to the Fedora team, updates will roll out gradually over time. The deployment of an update can also be stopped if the team discovers a problem in the new version.
Additionally, updates between Fedora versions are treated like any other update and are applied automatically without user intervention.
Another of its characteristics also allows the operating system to perform telemetry operations by default.
According to the development team, a service called "fedora-coreos-pinger" will periodically collect non-identifiable information about the machine, such as operating system version, cloud platform, and instance type and reports them to the servers controlled by the Fedora project.
In this case, the team confirms that a unique identifier will not be reported or collected.
Multiple virtualization and cloud platforms are not yet available. Only x86_64 is currently supported.
At the moment the startup of a Fedora CoreOS system is done live over a network (PXE). Closer integration projects are planned with Kubernetes distributions, including OKD.