Migrating from Proxmox to Incus: The Ultra-Lightweight Kernel-Level Container and VM Management Solution

Introduction: The Evolution of Infrastructure Virtualization

For years, Proxmox Virtual Environment (PVE) has been the go-to open-source platform for enterprise virtualization. It masterfully bridges the gap between traditional hypervisors and containerized workloads by supporting both Kernel-based Virtual Machines (KVM) and Linux Containers (LXC). However, as infrastructure demands shift toward hyper-efficiency, minimal overhead, and cloud-native agility, engineers are identifying systemic limitations in Proxmox’s heavy, Debian-based management stack.

Enter Incus—the community-driven, ultra-lightweight fork of LinuxContainers (LXD). Created following Canonical’s decision to restrict LXD’s licensing, Incus has rapidly evolved into a formidable alternative. It provides a streamlined, secure, and production-ready system container and virtual machine manager. This post explores why replacing Proxmox with Incus represents a paradigm shift toward high-performance, kernel-level infrastructure management.

Understanding Incus: The Lightweight Powerhouse

To appreciate Incus, one must understand its underlying philosophy. While Proxmox provides a complete, heavyweight operating system environment bundled with a dense web interface and clustering file systems (like Corosync and Ceph), Incus operates primarily as a system daemon. It leverages the host Linux kernel directly to orchestrate instances.

Key Architectural Differences

• True Kernel-Level Integration: Incus interacts natively with Linux namespaces, cgroups, and LSMs (Linux Security Modules) via LXC. This completely bypasses the user-space overhead introduced by Proxmox’s management wrappers.
• Unified Instance Management: Whether you are deploying an ultra-lightweight Linux Container (LXC) or a full hardware-virtualized Virtual Machine (via QEMU), Incus uses a singular, clean command-line interface (CLI) and REST API to manage both.
• Image-Based Workflows: Unlike Proxmox, which relies heavily on manual ISO installations or template extractions, Incus uses an image-driven deployment model similar to public cloud providers, drastically accelerating provisioning times.

Incus does not try to be an entire operating system; it is a highly optimized engine that transforms standard Linux servers into powerful, multi-tenant cloud infrastructure.

Why Move from Proxmox to Incus?

For organizations managing dense server environments, edge deployments, or localized dev-ops pipelines, the advantages of transitioning to Incus are profound.

1. Radical Resource Efficiency

Proxmox is notorious for its idle memory consumption. Even with no virtual machines running, the Proxmox GUI, pve-cluster services, and metrics daemons consume substantial RAM and CPU cycles. Incus, written in Go, runs as a highly efficient background daemon. In raw benchmarking, idle host machines running Incus consume a fraction of the RAM required by Proxmox, freeing up valuable hardware resources for actual production workloads.

2. Superior LXC Implementation

While Proxmox supports LXC, it treats containers as secondary citizens compared to KVM. Proxmox enforces a rigid structure on containers, often making advanced networking, nesting (running Docker inside LXC), and device passthrough cumbersome to configure. Incus natively treats system containers as its primary primitive. Nesting, GPU passthrough (NVIDIA/Intel), and complex storage mapping are achieved natively via single-line configuration shifts.

3. API-First Design and DevSecOps Integration

Proxmox’s API can be complex and challenging to automate without specialized providers. Incus was built from the ground up with a REST API-first architecture. Every action performed via the CLI is a direct call to its secure API. This makes integrating Incus into CI/CD pipelines, Terraform workflows, or custom internal control panels extraordinarily seamless compared to Proxmox.

Incus Architecture: Blending Containers and VMs

Incus expertly handles the duality of modern infrastructure requirements by offering two distinct types of instances under a unified management umbrella:

System Containers (LXC)

Unlike application containers (like Docker) which isolate a single process, Incus system containers isolate a complete, init-driven operating system. They share the host kernel but offer the security and operational characteristics of a virtual machine. This results in near-zero performance degradation, instant boot times, and massive density advantages over Proxmox KVMs.

Virtual Machines (KVM/QEMU)

When absolute kernel isolation or non-Linux operating systems (such as Windows or FreeBSD) are required, Incus seamlessly provisions traditional VMs. It leverages QEMU behind the scenes, applying the exact same network Profiles, storage volumes, and security policies used for containers. This eliminates the operational cognitive load of managing disparate systems.

Step-by-Step Transition Strategy

Transitioning from a production Proxmox cluster to Incus requires structured planning. Below is the high-level roadmap for a successful migration:

1. Audit and Export Workloads: Document your current Proxmox bridges, VLAN tags, storage backends (ZFS/Ceph), and instance IDs. Export raw disk images (.qcow2 or .raw) for VMs, and root filesystems for LXCs.
2. Prepare the Target Infrastructure: Install a clean Linux distribution (such as Debian, Ubuntu, or Rocky Linux) on your target hardware. Install Incus via production-ready repositories.
3. Initialize Incus: Run incus admin init to configure your storage pools (ZFS is highly recommended for snapshot efficiency) and network bridges (OVN or standard Linux bridges).
4. Ingest and Convert Instances: Use the official migration tools or manually import disk images into Incus using the incus import functionalities. For VMs, ensure the qemu-guest-agent is configured to maintain parity with Proxmox features.
5. Validate and Optimize: Apply Incus profiles to manage resource limits (CPU pinning, RAM caps) and verify network connectivity across your newly structured architecture.

Conclusion: The Future of Lean Virtualization

While Proxmox VE remains an excellent turnkey product for traditional data centers requiring an all-in-one graphical dashboard, Incus represents the future of lean, programmable infrastructure. By shedding user-space bloat and focusing on deep kernel-level integration, Incus enables enterprises to achieve unprecedented container density, exceptional VM speeds, and flawless automation workflows.

For organizations aiming to modernize their infrastructure, reduce hardware footprints, and embrace a cloud-native operative style, migrating to Incus is not just a viable alternative—it is a strategic upgrade.