Proxmox VE (Virtual Environment) is an open-source Type 1 hypervisor built on Debian. It runs KVM for full virtual machines and LXC for lightweight containers, managed through a web UI or API. The subscription model is optional — the community edition is fully functional without a paid license; the subscription gives access to the enterprise update repository and support.
Comparison
| Platform | License | VMs (KVM) | Containers | Clustering | Web UI |
|---|---|---|---|---|---|
| Proxmox VE | Open-source (optional sub) | Yes | Yes (LXC) | Yes | Yes |
| VMware ESXi | Commercial | Yes | No | Yes (vCenter) | Yes |
| Standalone KVM | Open-source | Yes | No | Manual | No |
| oVirt | Open-source | Yes | No | Yes | Yes |
Proxmox is the practical choice when you want VMware-style management without the licensing cost, or when you want to run both VMs and containers on the same node.
Core concepts
Node — a physical host running Proxmox VE. Managed independently or as part of a cluster.
Cluster — multiple nodes joined together. Share a unified management view and allow live migration of VMs between nodes. Uses Corosync for distributed consensus.
Quorum — clusters require a majority of nodes to be reachable to avoid split-brain. Minimum useful cluster size is 3 nodes (loss of one node still leaves a majority). Two-node clusters need a quorum device (qdevice) to function safely.
VM — full virtual machine backed by QEMU/KVM. Hardware-level isolation. Arbitrary OS.
Container (CT) — LXC container. Shares the host kernel; lower overhead than a VM. Linux-only. Useful for services where you want process-level isolation without a full OS.
Storage pool — where disks and images live. Supported backends: local directory, LVM, LVM-thin, ZFS, NFS, CIFS, and Ceph (via rbd). ZFS and Ceph are the most capable options for a cluster — ZFS for local redundancy, Ceph for shared storage across nodes.
Related
- Proxmox VE documentation
- Proxmox community forum
- Corosync documentation
- Ceph — distributed storage backend for Proxmox clusters
- OpenStack — the next tier up the scale spectrum
- Proxmox cluster in the homelab