Broadcom’s takeover of VMware turned a familiar line item into a budget emergency. Perpetual licenses are gone, replaced by per-core subscriptions with a 72-core minimum that took effect April 10, 2025 — and renewals have come back 800–1,500% higher. vSphere Foundation now starts around $4,500 per CPU per year; one widely-cited shop watched an Essentials Plus renewal jump from roughly $1,900/yr to over $14,000. Proxmox VE does the same core job — enterprise virtualization and clustering — for free, and version 9.1 (November 2025) ships a built-in ESXi import wizard that makes the move close to point-and-click.

What works the same

Proxmox VE is a complete type-1 hypervisor platform: KVM virtual machines and LXC containers, live migration, high-availability clustering, software-defined storage with Ceph and ZFS, snapshots, scheduled backups via Proxmox Backup Server, and a full web UI plus REST API. The things teams actually run vSphere for — consolidating workloads, moving VMs between hosts with no downtime, and surviving a node failure — are all here, with no per-core meter ticking in the background.

What you give up

VMware’s ecosystem is deeper. You give up vCenter’s polish, NSX networking, vSAN’s maturity, and a vast catalogue of certified third-party tools and VMware-specific expertise. Proxmox support is community-first; a paid subscription buys the enterprise repository and ticket support, but not the same global partner network. Some commercial backup, monitoring and DR products still treat VMware as the first-class citizen and lag on Proxmox.

The math

VMware vSphere Foundation: roughly $4,500 per CPU per year, with a 72-core purchase floor — a small datacenter easily clears $45,000/yr. Proxmox VE: $0 for the software; an optional support subscription runs about €115 per CPU per year (~$120) for the enterprise repo. For a modest 10-host setup that’s the difference between ~$45,000 and ~$1,000 a year. Break-even on migration effort usually lands inside the first year.

Migration — time & effort

Plan a weekend per cluster, not per VM. Proxmox VE 9.1’s ESXi import wizard connects to vCenter or a host, lists your VMs, and pulls them across — often live — so you’re not exporting OVAs by hand. Stand up Proxmox on one freed-up host, migrate a few non-critical VMs first, validate networking and backups, then roll the rest. Keep vSphere licensed until the last workload is verified.