Quick answer: KVM = a real virtual machine with its own kernel (can run Windows, Docker, custom kernels). OpenVZ = a container sharing the host kernel (Linux-only, no kernel control, and the classic way hosts oversell). All HostCraft VPS run KVM on Proxmox.
What a container-based "VPS" actually is
OpenVZ and LXC carve a Linux host into containers. Each container shares the host’s kernel — there is no separate operating system, just an isolated filesystem and process table on top of one shared kernel.
That architecture is why container "VPS" are cheap to oversell: RAM and CPU limits are soft, swap behavior is shared, and a noisy neighbor’s load is literally your load — the kernel scheduling your processes is the same one scheduling theirs.
What you can and can’t do on OpenVZ
Container VPS fail on a predictable list of workloads:
- Windows — impossible; there is no guest OS, only the host’s Linux kernel.
- Docker — historically broken or restricted inside OpenVZ; nested containerization needs kernel features you don’t control.
- Custom kernels/modules — no wireguard module loading, no kernel tuning, no swap control.
- FUSE, some VPNs, anything needing /dev/tun you don’t own.
What KVM gives you instead
KVM is hardware virtualization: the hypervisor presents each VM a full virtual motherboard, CPU, disk and network card. Your guest runs its own kernel — Ubuntu, Debian, AlmaLinux, or a licensed Windows Server install — completely independent of the host’s.
The practical result: dedicated RAM means allocated RAM (not a cgroup ceiling), Windows works, Docker works, and a neighbor’s kernel panic is their problem, not yours.
How to tell which you’re being sold
Providers rarely print "OpenVZ" on the marketing page. Three checks:
- Ask "can I run Windows?" — a no, or "Linux templates only", means containers.
- Run
systemd-detect-virtorhostnamectlon a trial VM — it printskvmoropenvz/lxcdirectly. - Suspiciously low prices on big RAM — container overselling is how ₹99 "4GB VPS" exist.
Where this matters most
For a WordPress site or a small bot, containers can be survivable. For Windows RDP desktops, production databases, game panels and anything where latency consistency matters, the shared-kernel trade-off shows up exactly at your peak hour.
Every HostCraft VPS tier runs KVM on Proxmox — which is also why licensed Windows Server ships on every plan instead of being an exception.
Related pages
- VPS & RDP plans — KVM tiers from $2.59/mo
- Linux VPS India — KVM Linux tiers
- Windows VPS India — licensed Windows on KVM
- How to check if your VPS is oversold — the companion test
FAQ
Is OpenVZ always bad?
Not always — for simple Linux sites it can work. But you can’t run Windows, Docker or custom kernels, and overselling is endemic on container platforms. Know what you’re buying.
How do I check my current VPS type?
Run systemd-detect-virt — it prints the hypervisor or container runtime directly.
Is KVM slower than containers?
Historically a few percent; with modern CPUs and virtio drivers the difference is negligible — and you gain real isolation, which is the entire point of a VM.
Why is Windows impossible on OpenVZ?
Containers share the host kernel — and the host kernel is Linux. Windows needs its own kernel, which requires hardware virtualization (KVM, VMware, Hyper-V).
Do any big providers still sell OpenVZ?
Fewer than five years ago, but budget hosts and resellers still do — usually without saying so on the pricing page. The Windows question is the fastest detector.