Have Proxmox set up as the base for container workloads - WZ-IT installs Proxmox VE on your existing or rented hardware: storage and network setup, backup integration, functional testing, documentation and handover. Docker stacks then run in VMs on this base. View the Proxmox setup · Docker applications without your own hypervisor: Coolify managed hosting
Proxmox is not the same thing as Docker, and the two are not competitors either. Proxmox VE is a virtualization platform, a hypervisor that runs full virtual machines (through KVM) and system containers (through LXC) on your own hardware. Docker is an application-container runtime that packages individual services from images and starts them (Docker Engine docs). Put simply: Proxmox provides the infrastructure that operating systems run on, and Docker packages the applications that run inside those operating systems. In practice you typically run Docker inside Proxmox, namely in a VM or an LXC container. The two technologies complement each other, they do not replace one another.
The confusion comes from the shared word "container". But the two mean different things: LXC are system containers (a complete, lightweight Linux userspace), while Docker containers are application containers (a single process plus its dependencies). That distinction explains the entire relationship between them. A detailed comparison of VMs and LXC is in LXC vs. KVM; Docker Compose, Coolify and Kubernetes are compared side by side in Kubernetes vs Docker Compose vs Coolify.
Proxmox and Docker solve different problems
Proxmox answers the question "what do my systems run on?" It consolidates physical servers, manages VMs and containers centrally through a web interface, and provides high availability, live migration, snapshots and backups. For the fundamentals, see What is Proxmox.
Docker answers the question "how do I ship and start my application?" It defines an image format that bundles an application with all of its dependencies reproducibly, plus a runtime that starts those images as isolated processes. Docker does not deal with hardware, clustering or failover, that is not its job.
In other words: Proxmox replaces VMware or Hyper-V. Docker does not replace Proxmox, it replaces the way you package and roll out software. A typical stack looks like this: a Proxmox cluster as the base, VMs as hosting units inside it, and Docker inside those VMs for the individual applications.
VM (KVM) vs. LXC container vs. Docker container
The three terms stand for three different isolation models. This table places them side by side:
| KVM VM (Proxmox) | LXC container (Proxmox) | Docker container | |
|---|---|---|---|
| Type | Full virtualization | System container | Application container |
| Kernel | Own guest kernel | Shared host kernel | Shared host kernel |
| Contains | Complete operating system | Lightweight Linux userspace | Single service plus dependencies |
| Guest OS | Linux, Windows, BSD and more | Linux only | Linux only (in the container userspace) |
| Isolation | Very strong (hardware level) | Medium (namespaces, cgroups) | Process level |
| Overhead | Higher (own kernel, RAM) | Very low | Very low |
| Managed by | Proxmox (KVM/QEMU) | Proxmox (LXC) | Docker Engine / Compose |
| Lifecycle | Long-lived ("pet") | Long-lived ("pet") | Disposable ("cattle") |
The key takeaway: VMs and LXC are hosting units that Proxmox manages directly. A Docker container is a deployment unit that Proxmox does not even see, it lives inside a VM or an LXC. For a detailed comparison of KVM and LXC, see LXC vs. KVM.
Can I run Docker on Proxmox?
Yes, and this is exactly how it is done in practice. There are two paths, with one clear recommendation.
Recommended: Docker in a VM
Create a VM in Proxmox with a Linux guest (Debian or Ubuntu LTS are proven choices) and install the official Docker Engine inside it. Proxmox recommends running application containers inside a QEMU VM for use cases requiring maximum isolation and live migration (container documentation). The VM also brings its own kernel; Docker features such as overlay2 storage, cgroups, namespaces and Docker's own iptables rules are therefore not subject to the constraints of an LXC container. You also benefit from VM snapshots, backups through Proxmox Backup Server and live migration in a cluster.
Best practices for the Docker VM:
- One dedicated VM per stack or tenant. Keep production Compose stacks separate from test and development environments.
- Provision enough RAM and disk. Docker images, volumes and logs grow; plan headroom and monitor utilization.
- Install qemu-guest-agent so Proxmox can drive consistent backups and clean shutdowns.
- Use a separate disk for Docker volumes, which simplifies backup and restore.
Backup and Data of the Docker VM
You back up the Docker VM like any other VM through Proxmox: a backup job writes it to a storage, preferably to a Proxmox Backup Server with incremental, deduplicated backups. Two points determine the quality of the backup. First, the qemu-guest-agent: if it is enabled (agent: 1) and running in the guest, Proxmox briefly freezes the file system for the backup in snapshot mode (guest-fsfreeze-freeze and guest-fsfreeze-thaw), which improves consistency. Snapshot mode has the lowest downtime but leaves a small risk of inconsistency; stop mode provides the highest consistency at the cost of a short downtime (Proxmox documentation: backup modes). Second, the separate disk for Docker volumes, which simplifies backup and restore. WZ-IT handles setup and operation of a PBS under Proxmox Backup Server setup and operations.
Possible, but handle with care: Docker in an LXC container
Docker can also run inside an LXC container. This saves resources because there is no second kernel and no VM overhead, and the container boots faster. The price is extra configuration and constraints. At minimum the container configuration needs the features nesting=1 and keyctl=1. Important pitfalls:
- Unprivileged containers are preferable from a security standpoint, but increasingly cause problems for Docker on recent kernels (conflicts between runc, user namespaces and kernel configuration). Expect rework or fall back to a VM.
- Not every application works. Because the LXC shares the host kernel, Docker workloads that need specific kernel modules, their own storage drivers or deep capability requirements will fail.
- No live migration with running processes the way a VM offers; LXC can only be migrated offline.
As a rough rule: labs, homelabs and simple single containers in LXC, production and complex stacks in a VM.
Note: installing the Docker Engine directly on the Proxmox host is a bad idea. Docker rewrites the host iptables, bridges and cgroups and can clash with the Proxmox firewall, cluster stack and networking. Keep the host lean and encapsulate Docker. c't (German) also advises against installing Docker or Podman on the host, because Proxmox and Docker can get in each other's way with network and firewall rules.
OCI images in Proxmox: a nice feature, not a Docker replacement
Since Proxmox VE 9.1 (November 2025), LXC containers can also be created directly from OCI images (Proxmox roadmap), the same image format Docker uses. This is convenient for simple, stateless services. However, the Proxmox documentation still classes running application containers as a technology preview; the container uses the existing LXC framework (Proxmox documentation: Linux Container). It does not replace a full Docker or Compose environment with networks, volumes and multi-container orchestration; the roadmap names extending OCI support and managing multi-container applications according to the Compose specification as goals. An independent hands-on test with pitfalls is described by c't in Ausprobiert: OCI-Images in Proxmox Virtual Environment (German). For production application stacks, a VM running the official Docker Engine remains the recommended standard. As of October 2026, the current release is Proxmox VE 9.2 (released May 2026), based on Debian 13 Trixie.
Docker, LXC or VM: When Do I Use Which?
- Proxmox (VM or LXC) directly, when you need whole operating systems: Windows servers, databases with fixed configuration, legacy applications, domain controllers, firewalls or classic Linux servers.
- Docker (inside a Proxmox VM), when your applications ship as images, you want reproducible deployments, you use CI/CD, or you run microservices and modern web stacks.
- Kubernetes (across several Proxmox VMs), when you orchestrate many containers across multiple nodes, want automatic scaling and self-healing. Proxmox provides the VMs, Kubernetes the orchestration; setup and operations are described in Kubernetes on Proxmox, the distinction from Docker Compose and Coolify in Kubernetes vs Docker Compose vs Coolify.
So the decision is rarely "either or". It almost always reads: Proxmox as the foundation, and on top of it, depending on the application, VMs, LXC and Docker in the right combination.
Running Docker on Proxmox: Backup, Updates, Support
Cleanly separating the hypervisor, the VMs and the container runtime is what determines whether a platform stays maintainable over the long term: updates run separately on the Proxmox host, in the VM's guest operating system and for the container images, and backups cover the VM including the Docker volumes. Depending on your starting point, there are three routes:
- Have the Proxmox base set up: WZ-IT installs Proxmox VE on your existing or rented hardware, from a single node to a three-node cluster, with storage and network setup, backup integration and technical handover. You then set up the Docker VMs on top.
- Container applications without your own hypervisor: if you only want to run Docker applications, you can run them through Coolify managed hosting, without Proxmox infrastructure.
- Kubernetes on Proxmox: the guide Kubernetes on Proxmox describes architecture, VM layout and operations.
An overview of setting up and running Proxmox is on the Proxmox & Private Cloud page. For a no-obligation conversation, book a free initial consultation directly.
