KVM. atomos-cli. Electros.

AtomOS:
The Linux hypervisor
for your servers

Family 1.11.0. KVM, QEMU and libvirt on AlmaLinux, installed with atomos-cli as compute, storage, or both. Electros is the fleet screen. The hypervisor stays free.

Install with atomos-cli Get it now

KVM, QEMU, libvirt

Compute runs on AlmaLinux. atomos-cli installs Compute, Storage, or Full. Ubuntu and Debian are documented for storage only.

GPU passthrough

PCI passthrough can hand a physical GPU to a guest. Partitioned GPUs are not in this release. Validate the GPU and driver on your hardware.

Governed from Electros

Electros registers the host, checks the certificate, and runs the VM workflow. The host itself is still Linux, atomos-cli, and libvirt.

The Next-gen Linux Hypervisor you were waiting for

No need to be fancy to be just right. At Elemento, we believe in the Linux paradigm. We didn't want to reinvent virtualization from scratch, forgetting all the great work behind KVM and QEMU over the past 30 years.


Instead, we built on top of KVM and QEMU to create AtomOS, a hypervisor that is open, portable, and secure.

  • RHEL-compatible base: AlmaLinux for compute and full installs
  • Three roles from atomos-cli: Compute, Storage, or Full
  • GPU PCI passthrough — validate the card, driver, and IOMMU group
  • C4 discovers capacity. It does not by itself provide quorum, fencing, or failover
  • Fleet workflow in Electros, host operations on the machine
Get Started Book a call

Electros runs the fleet. The local UI runs one server.

Electros is the desktop for every registered AtomOS host. The local console is the machine you are on.

Many hosts
Electros Desktop. Every registered host.
Host A AtomOS
Host B AtomOS
Host C AtomOS
Open Host C
Local UI This server only.
  • atomos-cli
  • systemd
  • libvirt and KVM

The local console lists this machine. Electros lists Host A, Host B, and Host C.

One install command. Three roles.

atomos-cli --install Compute

Compute

AlmaLinux. Virtual machines on this host.

atomos-cli --install Storage

Storage

AlmaLinux, Ubuntu, or Debian. Volumes on this host.

atomos-cli --install Full

Full

AlmaLinux. Compute and storage on the same host.

What 1.11.0 actually ships

From the 16 October 2026 technical manual.

Documented

Compute, storage, vaults

KVM virtual machines, volumes, and the host bridge are the baseline. Install Compute, Storage, or Full with atomos-cli. A vault module is not a configured pool until you create it.

Documented

Two admin planes

Electros registers every host in the fleet. atomos-cli stays on the single machine.

Documented

GPU PCI passthrough

A physical GPU can be assigned to a guest when IOMMU groups allow it. Partitioned GPUs, MIG, and SR-IOV are not part of this release.

Prove it on your build

Live migration and load balancing

Live migration needs matching CPUs, shared storage, and a network path. Dynamic load balancing exists on suitable builds. Measure the trigger, pinning, and maintenance window before you rely on it.

Prove it on your build

Hot CPU and RAM

Hot add is implemented. Windows guests do not support hot-unplug of CPU or RAM. A successful API call is not proof the guest is using the new size.

Prove it on your build

Backup and Veeam

Integration components exist. A certified restore runbook does not. Test full and file restore, including a database, on the Veeam and AtomOS versions you will run.

Install with atomos-cli Get your free licence

AlmaLinux underneath. Not a fork.

Compute and full installs use AlmaLinux. A Red Hat hardware catalogue is evidence about the OS, not an AtomOS certification.

Compute and full installs use a supported AlmaLinux 9 release. The October 2026 guide uses 9.8. Do not treat that as support for 10.x.


A Red Hat hardware catalogue describes the operating system. It is not an AtomOS certification of your server, GPU, or NIC.

  • AlmaLinux for Compute and Full
  • Ubuntu and Debian for storage-only, on documented versions
  • SUSE is still a lab combination
  • Recommended sizing starts at 16 GB RAM and 8 threads

Check the build

Install an AlmaLinux release the chosen AtomOS build actually supports. Confirm hostname, DNS, NTP, and a clean reboot before you run atomos-cli.

Prove the hardware

Confirm the kernel sees virtualization, disks, NICs, and the IOMMU groups you need. A catalogue entry is not a passthrough test.

1.11.0

Reference family
Manual updated 16 October 2026. Check the build you install.

3

Install roles
Compute, Storage, or Full

€0

Hypervisor licence
Support plans are optional

9

AlmaLinux
Compute and full. Not 10.x.

Install with atomos-cli

Inspect the bootstrap script, then install Compute, Storage, or Full. The help on the build you installed wins if it differs from this page.

AtomOS Installation Guide
1. Install the operating system for the role:
  • Compute or Full: a supported AlmaLinux 9 release. The October 2026 guide uses 9.8.
  • Storage-only: documented Ubuntu or Debian releases, or AlmaLinux 9.
2. Save the bootstrap, read it, then run it:
curl -fsSL https://repo.elemento.cloud/get-atomos.sh -o /tmp/get-atomos.sh
less /tmp/get-atomos.sh && sudo bash /tmp/get-atomos.sh
Now you can use the AtomOS CLI to install AtomOS
Install the AtomOS services
The documented role names are Compute, Storage, and Full, with on-prem. If atomos-cli --help differs, follow the installed build.
3. Install for a storage-only node:
sudo atomos-cli --install Storage on-prem
3. Install for a compute-only node:
sudo atomos-cli --install Compute on-prem
3. Install for a complete AtomOS version:
sudo atomos-cli --install Full on-prem
4. Follow AtomOS CLI indications to conclude the configuration:
  • Optional modules such as ZFS, GlusterFS, Lazydocker, and NVMe-oF. Installing a module does not create the pool.
  • Setup the storage
  • Setup the network
5. Reboot the host.
6. Install Electros on your PC or Mac to launch and manage VMs from anywhere
Reboot, then check the host with atomos-cli --check before you place a workload.

What you operate on the host

Documented host capabilities from the 1.11.0 manual. Each one still needs a test on the build you install.

Volumes

Virtual machines use volumes on the host. qcow2 is the thin format to validate with the storage you choose.

Live migration

Possible when CPUs match, storage is shared, and the network path is there. Measure it before you schedule maintenance around it.

Hot CPU and RAM

Hot add is implemented. Windows guests do not support hot-unplug of CPU or RAM.

atomos-cli

Install, bridge setup, status, and the cluster secret are host commands. Electros does not replace the machine's own Linux admin.

Load balancing

Dynamic placement exists on suitable builds. Confirm the trigger, pinning, and the maintenance window on your cluster.

Storage modules

The wizard can offer ZFS, GlusterFS, Lazydocker, and NVMe-oF. Ceph needs an explicit compatibility check. Installing a module does not configure the pool.

You-Know-Who vs AtomOS — Hypervisor Showdown

How AtomOS compares to the industry-leading virtualization platform

Feature Vmware VSphere Elemento AtomOS
Hypervisor Class Type 1 Type 1
Operating System Proprietary Kernel Almalinux (RHEL binary compatible)
Virtualization Engine Proprietary Closed-Source Upstream "Vanilla" KVM/QEMU
Management vCenter Server VM Electros dashboard & REST API
Licensing Commercial, CPU-based Server-based (not CPU cores or VM count)
Cluster Setup Manual w/ License C4 publishes capacity. Failover is a separate test.

Compare Costs — AtomOS vs VMware

The hypervisor licence is €0 per server. Compare that with a VMware licence on the same hardware.

Standalone calculator page →

Prove the guest you will run

The 1.11.0 manual does not publish a certified guest matrix. KVM can boot many Linux and Windows systems. Windows does not support hot-unplug of CPU or RAM.

Linux Distributions

Ubuntu 24.04+ Debian 12+ AlmaLinux Rocky Linux Fedora 38+ Pop!_OS Mint CentOS FireBoxV Arch Linux Gentoo OpenSUSE OpenBSD FreeBSD NetBSD Other Linux guests — test them

Windows Support

Windows XP (EOL) Windows 7 (EOL) Windows 10 Windows 11
Server 2003 (EOL) Server 2008 (EOL) Server 2012 (EOL) Server 2016 (EOL) Server 2019 Server 2022 Server 2025

MacOS Support

Work in progress...

Storage you configure

Installing a module does not create the pool. Ceph stays off until that build has been validated.

ZFS and GlusterFS

The install wizard can offer these modules. A module on disk is not a pool, an export, or a shared filesystem.

NVMe-oF and iSCSI

The manual lists them among storage paths to design. Confirm the network, the target, and a reboot before you place virtual disks there.

Ceph

Leave Ceph disabled until you have an explicit compatibility check for the AtomOS build you are running.

C4 finds capacity. It does not fail over for you.

Hosts publish what they can run. A client can ask for a match. Quorum, fencing, and automatic VM restart are a separate test.

C4 is the discovery and capability layer. Hosts advertise capacity. That visibility is not the same as permission to place a workload, and it is not high availability.

Key Benefits:

  • Hosts advertise capacity. Multi-node installs share one cluster secret
  • Electros still decides which connection is active
  • Failover, fencing, and split-brain behaviour must be tested on your cluster
  • A single host has no intrinsic high availability
Learn More About Technology

Discovery, then a decision

C4 can help place a workload on a compatible host. It does not elect a leader or fence a failed node for you.

AtomOS is Free, Forever

The full hypervisor is free on every server — you only pay for optional support

AtomOS — Free Forever

€0

Per server, regardless of CPU cores or VM count

  • ✓ No per-VM or per-core hypervisor licence
  • ✓ Local console for that server, Electros for the fleet
  • ✓ atomos-cli on the host
  • ✓ Live migration — validate CPU, shared storage, and network on your build
  • ✓ Host administration with Linux, systemd, and libvirt
  • ✓ Optional support plans, sold per server
Download Now

Optional Support Plans

Per server, per year — all plans include 8x5 coverage

Base

€1,200/server/year

8x5 coverage

  • ✓ Email ticketing support
  • ✓ 8x5 coverage (business hours)
  • ✓ Guaranteed upgrade path
Get Base Support

Pro

€2,000/server/year

8x5 coverage

  • ✓ Everything in Base
  • ✓ Phone & call support
  • ✓ Support in Italian and English
  • ✓ 8x5 coverage (business hours)
Get Pro Support

24x7

Custom

Around-the-clock coverage

  • ✓ Everything in Pro
  • ✓ 24x7 coverage
  • ✓ Tailored SLAs for your workloads
Contact Sales

Per-Server Support Pricing Drives Green Economy

Our support model incentivizes efficient resource utilization and sustainable infrastructure choices

Efficient Resource Utilization

Unlike CPU-core or VM-count based licensing, AtomOS's per-server support pricing encourages organizations to maximize the value of each physical server. This drives investment in larger, more efficient hardware that can host more workloads with better performance per watt.

Green Economy Benefits:

  • Incentivizes high-density, energy-efficient servers
  • Reduces power consumption through consolidation
  • Lower total cost of ownership and operational expenses
  • Extends hardware lifecycle through better utilization

Sustainable Infrastructure

By pricing support per server rather than per CPU core or VM, we encourage organizations to choose powerful, efficient hardware that can handle more workloads with less energy consumption.

Result: Fewer servers, less power, lower carbon footprint

Frequently Asked Questions

Common questions about AtomOS deployment and usage

Which operating system does AtomOS install on?

Compute and full installs use a supported AlmaLinux 9 release. The October 2026 guide uses 9.8 and does not extend that to 10.x. Ubuntu and Debian are documented for storage-only. SUSE is still a lab combination.

Can I pass a GPU to a virtual machine?

PCI passthrough is the documented path, and it depends on IOMMU groups, the GPU, and the driver. Partitioned GPUs are not in this release. Prove the card on the hardware you will ship.

Does clustering fail over by itself?

No. C4 discovers capacity. Quorum, fencing, fault detection, and automatic VM restart are still a test you run. A single host has no intrinsic high availability.

How do Electros and the host split the work?

Electros registers the target, checks the certificate, and runs the VM workflow. The machine itself is administered with Linux, atomos-cli, systemd, and libvirt.

Is Veeam a certified backup?

Integration components are available. Restore of a whole VM or a single file still has to be measured on your Veeam build, guest, and AtomOS version. RAID is not a backup.

Is the hypervisor free?

Yes. The AtomOS hypervisor licence is €0 per server. Optional support plans are separate. Check the installed component versions before you treat a procedure as supported.

Complete Your Cloud Infrastructure

AtomOS works with Electros — and Atomosphere connectivity — to create a complete cloud platform

Electros

Electros

Orchestration dashboard for managing VMs across private clouds and existing CSP accounts from a single interface.

Learn About Electros
Atomosphere

Atomosphere

Connectivity technology behind Electros — a unified API over private clouds and your existing CSP accounts.

How connectivity works

Run KVM on your servers. Govern the fleet from Electros.

The hypervisor licence is €0 per server. Support plans are optional.

Buy AtomOS Download Free Edition Book a call