Virtualization Concepts

These pages cover the foundational ideas behind virtualization. They explain the models, the tradeoffs, and what is actually happening inside a running VM or container — before getting into platform-specific setup.

In This Section

• Virtualization Fundamentals — the core models, the differences between full virtualization and containers, and how to choose between them.
• VM Architecture — how QEMU and KVM divide the work, what a guest really sees, and which defaults are worth keeping.
• LXC and OCI Containers — what LXC system containers are, how OCI containers differ, and where each fits in a Proxmox-based homelab.
• Docker — what Docker actually is, how images and layers work, how to run it sensibly in a homelab, and when it earns its place over LXC.
• Podman — Docker without the root daemon: rootless containers, systemd integration, and when the security tradeoff matters.
• VirtualBox — Oracle's desktop hypervisor, where most homelab journeys start, and why most people eventually move on.
• systemd-nspawn — the container runtime that ships with systemd: no daemon, no image layers, tight host integration.
• VMware ESXi — the enterprise hypervisor that dominated data centres, what Broadcom did to it in 2024, and why many people moved to Proxmox.

Suggested Reading Order

Start with Fundamentals for the mental model, then VM Architecture for QEMU/KVM mechanics, then LXC and OCI for the container standards picture. Read Docker and Podman back to back — they make more sense as a pair. VirtualBox, systemd-nspawn, and ESXi can be read in any order as standalone reference pages.