KVM, LXC: the difference in 5 minutes

If you read our SolusVM vs. Proxmox guide, you already know the basic idea: virtualization splits a physical server into several independent servers. What we didn't cover there is that there are two different ways to do that split — and they're called KVM and LXC.

This isn't an academic detail: if you're going to use a VPS with Proxmox, every time you create a server the panel will ask you which of the two you want. This guide exists so you can answer that question with confidence, in five minutes.

KVM: the apartment with its own utilities

KVM (Kernel-based Virtual Machine) is the standard virtualization technology in the Linux world, and the one we use on all Capa7 VPS. It creates full virtual machines: each one has its own operating system, its own kernel, and dedicated virtual hardware.

Going back to the building analogy: a KVM VM is an apartment with fully independent utilities — its own plumbing, its own electricity, its own heating. Nothing is shared with the neighbors beyond the building's structure. That gives you:

• Strong isolation — what happens in one VM doesn't affect the others

• Full freedom of operating system: AlmaLinux, Ubuntu, Debian... or Windows Server

• Its own kernel — you can load modules, fine-tune the system deeply, and run Docker without surprises

The cost of that independence: each VM loads a complete operating system, so it uses more RAM and disk, and takes longer to boot than a container.

LXC: the office in a coworking space

LXC (Linux Containers) takes a different approach: instead of simulating a full machine, it creates an isolated space that shares the host system's kernel. It's like a private office in a coworking space: you have your own key, your own space, and your own furniture — but the electricity, climate control, and structure belong to the building.

Since it doesn't load a whole operating system, an LXC container:

• Boots in seconds, not minutes

• Uses very little extra RAM — almost all of it goes to your application

• Lets you fit far more containers than VMs on the same hardware

Its limits are the flip side of the same coin: it only runs Linux (it shares the host's kernel, which is Linux), and its isolation — although very good — is weaker than that of a full VM, because that kernel is shared.

The comparison, side by side

So what do we use at Capa7?

All our VPS — High Performance, Basic, Windows, cPanel/WHM — are delivered as KVM virtual machines: strong isolation and guaranteed resources, on Dell servers with Intel Xeon and NVMe in our Boca Raton, Florida datacenter.

And LXC? That's where VPS Proxmox comes in: we deliver a VPS with Proxmox VE installed, and inside it you create whatever you want — KVM VMs and LXC containers, mixed together. It's the most affordable way to have both technologies under your control, without buying hardware.

Questions we hear often

Is Docker the same as LXC?
They're related: both are Linux containers that share the kernel. The difference in approach is that an LXC container behaves like a lightweight, complete system (with its own services, users, IP), while Docker packages a single application with its dependencies. If your goal is to run Docker, the usual approach is to do it inside a KVM VM.

Is a container less secure than a VM?
Its isolation is weaker because it shares the kernel — for separating your own services from each other, it's more than enough; for giving access to third parties you don't trust, a KVM VM is the prudent choice.

Can I run KVM and LXC together?
Yes — that's exactly what Proxmox VE does: in the same panel you create a Windows VM with KVM and, right next to it, three LXC containers for your Linux services. Our VPS Proxmox comes ready for that.

I signed up for a regular VPS — which one did I get?
If it's from Capa7, it's a KVM VM: guaranteed resources and full isolation. You'll only see LXC if you manage your own Proxmox hypervisor.

Capa7 Team

17 years managing hosting, VPS, and dedicated servers on our own infrastructure in Boca Raton, Florida. We write the way we'd like things explained to us: clear and no fluff.