How Proxmox Works - Nuface Blog

🔰 Introduction

After Broadcom acquired VMware, the company dramatically changed its licensing model — shifting from perpetual to subscription-based plans.
This move significantly increased the total cost of ownership (TCO) for many enterprises, prompting IT teams to explore open-source alternatives.

Among these, Proxmox VE (Virtual Environment) has gained strong attention as a robust and cost-effective replacement for VMware’s virtualization stack.
This article explains the architecture and working principles of Proxmox, and evaluates its potential as a VMware substitute.

🧩 1. What Is Proxmox VE?

Proxmox VE (Virtual Environment) is an open-source virtualization management platform based on Debian Linux.
It integrates two core virtualization technologies:

Technology	Purpose	Key Features
KVM (Kernel-based Virtual Machine)	Provides full virtualization for Windows or Linux systems.	Comparable to VMware ESXi, supports snapshots, live migration, and dynamic resource allocation.
LXC (Linux Containers)	Provides lightweight OS-level virtualization.	Low overhead, fast startup, ideal for Linux services and microservice environments.

Proxmox unifies both under a single management interface — Web GUI, CLI, and REST API — and includes ZFS storage, cluster management, backup, and high availability (HA) natively.

⚙️ 2. Overall Architecture

A simplified conceptual stack looks like this:

User Interface (Web GUI / API)
        │
Proxmox Management Layer (pvedaemon / pvestatd / pve-cluster)
        │
Virtualization Layer (KVM for VMs / LXC for Containers)
        │
Storage Layer (ZFS / Ceph / iSCSI / NFS / LVM)
        │
Physical Hardware (CPU / RAM / Disk / NIC)

Key Components:

pvedaemon / pvestatd / pveproxy – Core management daemons that handle user commands, statistics, and REST API calls.
QEMU / KVM – Execute virtual machines, enabling full hardware virtualization (CPU, RAM, storage, networking).
LXC Daemon – Manages container lifecycle and isolation through cgroups and namespaces.
Storage Plugins – Integrate various storage backends such as ZFS, Ceph, NFS, or LVM.

🖥️ 3. Virtualization Layer: KVM & LXC

🧱 KVM Virtual Machines

Each VM runs as a separate QEMU process on the host.
Utilizes Linux’s built-in KVM kernel module for hardware acceleration.
Supports snapshots, backups, and live migration — similar to VMware vSphere.

💡 Ideal for running full guest operating systems with complete isolation.

🧩 LXC Containers

Share the host kernel while maintaining isolated file systems and networks.
Launches in seconds and uses fewer resources.
Perfect for lightweight Linux workloads such as Nginx, Postfix, MySQL, or GitLab Runner.

💡 Think of it as “system containers,” not image-based like Docker.

🗄️ 4. Storage & Backup Mechanism

Storage Options

Proxmox uses a unified Storage Plugin Framework to manage diverse backends:

Local disks or ZFS pools
NFS, iSCSI, or Ceph clusters
Proxmox Backup Server (PBS) for remote or deduplicated storage

Backup Process

Uses snapshot-based backups, allowing online backups without downtime.
When integrated with PBS, it supports incremental backup and data deduplication.
Backup files are stored in .vma.zst format (compressed image archives).

🧠 5. Cluster & High Availability (HA)

Proxmox’s clustering and HA are built-in and based on Corosync messaging.

Feature	Description
Cluster Management	Manages multiple nodes under a unified interface.
HA Manager	Automatically restarts VMs or containers on another node if one fails.
Live Migration	Moves running VMs between nodes without interruption.

💡 When combined with Ceph or ZFS replication, it provides enterprise-grade fault tolerance.

📡 6. Network Architecture

Proxmox networking relies on standard Linux networking components:

Linux Bridge — Functions similarly to VMware’s vSwitch.
Supports VLANs, bonding, and VXLAN for complex topologies.
Includes optional SDN plugin for multi-tenant environments.

Example configuration:

auto vmbr0
iface vmbr0 inet static
    address 192.168.10.10/24
    gateway 192.168.10.1
    bridge-ports eno1
    bridge-stp off
    bridge-fd 0

⚖️ 7. Comparison: Proxmox vs VMware

Category	Proxmox VE	VMware vSphere / ESXi
Licensing	Free (optional enterprise subscription)	Subscription only (high cost)
Base Platform	Debian Linux + KVM/LXC	Proprietary ESXi hypervisor
Management	Web GUI / CLI / REST API	vCenter + ESXi Web UI
Backup	Built-in (ZFS / PBS)	Requires third-party tools like Veeam
HA & Cluster	Native via Corosync	Requires vCenter + HA license
Container Support	Native LXC	Requires Tanzu or external integration
Maturity	Stable and community-driven	Enterprise-grade but closed source

🔎 8. Can Proxmox Replace VMware?

For organizations that primarily need:

Server virtualization for Windows and Linux
Private cloud infrastructure
Lab or testing environments
Mixed VM + container workloads

➡️ Yes — Proxmox VE can effectively replace VMware vSphere + vCenter.
It delivers comparable core functionality, including HA, live migration, and centralized management.

Considerations:

If your infrastructure relies on deep VMware integrations (e.g., SRM, NSX, vCenter APIs), migration requires redesign.
For enterprise-level support, Proxmox Enterprise Subscription is available with commercial updates and support access.

✅ Conclusion

As Broadcom’s licensing changes push VMware costs upward, Proxmox VE emerges as a powerful open-source alternative that combines performance, flexibility, and cost efficiency.

It offers the essential virtualization capabilities — from KVM VMs to LXC containers, HA clustering, ZFS storage, and integrated backup — all under a single, transparent platform.

If your organization values freedom, scalability, and sustainability,
Proxmox VE is one of the most capable and future-proof replacements for VMware.