Migrating from Proxmox to Incus: The Ultra-Lightweight Kernel-Level Container and VM Management Solution
Introduction: The Changing Landscape of Virtualization
For years, Proxmox Virtual Environment (PVE) has been the undisputed champion of open-source virtualization for small to medium enterprises. By combining Kernel-based Virtual Machines (KVM) and Linux Containers (LXC) into a single, web-managed platform, Proxmox provided a robust alternative to costly proprietary hypervisors. However, as infrastructure demands shift toward edge computing, microservices, and maximum hardware efficiency, the operational overhead of traditional hypervisors is coming under intense scrutiny.
Enter Incus. Born as a community-driven, production-ready fork of Linux Containers (LXD) under the Linux Containers project, Incus is rapidly emerging as the premier alternative to Proxmox. While Proxmox excels as a heavy, feature-rich hypervisor suite, Incus offers an ultra-lightweight, kernel-level management solution designed for modern, automation-first infrastructure. This comprehensive guide explores why forward-thinking DevOps engineers and system administrators are replacing Proxmox with Incus, and how it redefines resource efficiency.
---Understanding Incus: The Evolution of LXC and LXD
To understand the value of Incus, one must understand its lineage. Incus is the modern continuation of the LXD ecosystem, created to ensure a fully open-source, community-driven future for container and virtual machine management. Unlike application containers like Docker, which isolate a single process, Incus focuses on system containers via LXC, alongside full hardware virtualization via QEMU.
Incus operates as a system daemon that exposes a powerful, secure REST API. Through this API, administrators can seamlessly manage hundreds of containers and virtual machines across single nodes or massive clusters. It provides a unified interface where a lightweight system container behaves exactly like a full virtual machine, but without the crippling performance penalties of hardware emulation.
---Proxmox vs. Incus: Architectural Differences
Choosing between Proxmox and Incus isn't just about comparing feature checklists; it is about fundamentally different architectural philosophies.
1. Monolithic Suite vs. API-Driven Daemon
Proxmox is a monolithic, Debian-based distribution. It bundles web interfaces, clustering engines (Corosync), filesystem managers (ZFS/Ceph), and backup tools into a tightly integrated operating system. While convenient, this creates a heavy footprint and binds you to Proxmox's specific release cycles and configuration structures.Conversely, Incus is a lightweight daemon that can be installed on top of almost any modern Linux distribution (Debian, Ubuntu, AlmaLinux, Rocky Linux, etc.). It does not dictate your OS, your storage backend, or your networking stack. It exposes a clean API, allowing it to integrate seamlessly into existing CI/CD pipelines, infrastructure-as-code (IaC) workflows, and custom orchestration platforms.
2. The Resource Overhead Reality
Proxmox relies heavily on its web GUI and underlying management services, which consume non-trivial CPU and RAM even at idle. Incus, operating directly at the kernel level, introduces virtually zero idle overhead. System containers managed by Incus share the host kernel directly, meaning a container can launch in milliseconds and utilize 100% of the raw hardware performance.
---Key Advantages of Replacing Proxmox with Incus
For organizations prioritizing agility, density, and automation, migrating to Incus yields several clear advantages:
- Ultra-Lightweight Efficiency: Because Incus leverages native Linux kernel features (namespaces, cgroups, LSMs), system containers run at bare-metal speeds. You can achieve significantly higher density, running up to 3x more workloads on the exact same hardware compared to traditional hypervisors.
- True Multi-Tenancy and Security: Incus was designed from the ground up with unprivileged containers as the default. By shifting User IDs (UIDs) and Group IDs (GIDs) at the kernel level, even if a malicious actor breaks out of a container process, they possess absolutely no privileges on the host system.
- Seamless Mixed Workloads: Need the absolute isolation of a traditional VM? Incus handles full virtual machines using QEMU with the exact same CLI commands and API endpoints used for system containers. You get the best of both worlds under a single management plane.
- API-First and IaC Ready: Managing Proxmox via automation often requires complex API wrappers or specialized providers. Incus features a first-class, well-documented REST API, native Terraform/OpenTofu providers, and excellent Ansible integration, making it a dream for DevOps teams.
- Simplified Clustering: Setting up a Proxmox cluster requires strict quorum rules and can be fragile on smaller scales. Incus includes built-in clustering powered by an embedded dqlite (distributed SQLite) database. Expanding a cluster is as simple as running a single join command.
Performance Comparison: At a Glance
To visualize the architectural efficiency, let us look at how the two platforms handle core system functions:
| Feature / Metric | Proxmox VE | Incus |
|---|---|---|
| Architecture | Monolithic OS Suite | Lightweight API Daemon |
| Primary Workload | KVM (VM-heavy) | LXC (Container-heavy) + QEMU |
| Idle Memory Footprint | Moderate (~1GB+ for OS/GUI) | Extremely Low (~Tens of MBs) |
| Container Boot Time | Seconds | Milliseconds |
| Configuration Management | GUI-centric / Config Files | API-driven / Infrastructure as Code |
| Host OS Choice | Strictly Proxmox (Debian base) | Any modern Linux distribution |
How to Transition: The Migration Path
Making the switch from Proxmox to Incus does not require rebuilding your entire architecture from scratch. Because Proxmox uses standard LXC configuration files and raw/qcow2 disk images for VMs, migrating data is highly scriptable.
- Assess Your Workloads: Identify which Proxmox VMs are candidates for system containers. Most Linux-based VMs running web servers, databases, or microservices can be converted into ultra-lightweight Incus containers, instantly freeing up massive amounts of RAM.
- Export Virtual Disks: Proxmox backing storage (whether on ZFS, Ceph, or LVM) can be exported using standard QEMU tools.
- Import to Incus: Use the powerful
incus-migratetool or native CLI commands to import raw disk images or filesystem roots directly into Incus storage pools. - Layer Your Automation: Replace Proxmox API scripts with clean declarative Terraform files or Ansible playbooks to manage your new Incus resources.
Conclusion: Is Incus Right for Your Business?
Replacing Proxmox with Incus is not merely a trend; it is a strategic shift toward lean, high-performance infrastructure. If your organization relies heavily on a point-and-click web interface and requires a turnkey virtual desktop infrastructure (VDI), Proxmox remains an excellent choice.
However, if your goal is to build a highly scalable, automated, and ultra-efficient infrastructure that maximizes bare-metal performance while minimizing software bloat, Incus is the definitive solution. By moving management to the kernel level, Incus proves that the most powerful hypervisor is the one you barely notice is there.