Virtualization: Part 3 — VMware vSphere and ESXi

VMware vSphere has long been the standard for enterprise virtualization. The platform consists of the hypervisor ESXi, which is installed directly on the server, and the management server vCenter, which groups hosts into clusters. After VMware was acquired by Broadcom in 2023, the terms of sale changed completely, and the product has been unavailable in Russia since 2022. So this article about VMware is primarily about what changed and how to migrate.

How vSphere is structured

• ESXi — a Type 1 hypervisor: runs on the server instead of an operating system and hosts virtual machines.
• vCenter Server — central management: inventory of hosts and VMs, templates, permissions, monitoring.
• Cluster features:
  • vMotion — move a running VM between hosts without downtime;
  • HA — restart VMs on other hosts when one fails;
  • DRS — automatic load distribution between hosts;
  • Fault Tolerance — a synchronous copy of a VM on another host for systems that cannot tolerate even a short restart.
• vSAN — distributed storage on the disks of the hosts themselves.

Most of these features require vCenter and a paid subscription.

What changed under Broadcom

• Perpetual licenses are no longer sold. Since early 2024 VMware is sold only by subscription. Support (SnS) under old perpetual contracts is serviced until the end of the contract term, but in many cases is not renewed. After it ends, ESXi and vCenter continue to run, but security fixes and updates no longer arrive.

• The catalog was pared down to several packages: VMware Cloud Foundation (VCF), vSphere Foundation (VVF), vSphere Standard and vSphere Enterprise Plus. Subscriptions are counted per CPU core with a minimum of 16 cores. For many companies, especially smaller ones, the cost compared to previous perpetual licenses has increased many times.

• The free ESXi was removed, then returned with limitations. The free hypervisor was removed in early 2024, and on April 11, 2025 it was made available again with ESXi 8.0 Update 3e. Conditions:

  • no more than 8 virtual CPUs per VM and no more than two physical CPUs per host;
  • cannot connect to vCenter — no vMotion, DRS, HA or backups via VADP;
  • cannot manage the host via the API;
  • can be downloaded only from the Broadcom support portal after registration.

  This is enough for a lab, but not for production infrastructure.

• Support for vSphere 7 ended. General support for vSphere 7.x, ESXi 7.x and vCenter 7.x ended on October 2, 2025. Security fixes for that branch are no longer released.

VMware and Russia

In March 2022 VMware suspended all sales, support and professional services in Russia, including support for cloud platforms, and then closed its Russian office. A Russian company cannot buy a subscription, renew support or officially receive updates. Installations that continue to run accumulate unpatched vulnerabilities over time — especially on the 7.x branch, whose support has ended.

Where to move

• Proxmox VE — a free platform based on KVM with a web interface, clustering, live migration and backups. Starting with version 8, Proxmox VE has a VM import wizard directly from ESXi hosts: it connects to ESXi as a datastore and transfers machines with a choice of storage and network on the new side.

• Russian platforms from the registry of domestic software — if certification or government procurement requirements are needed. Examples:

  • zVirt (Orion soft) — based on oVirt and KVM, in the registry since 2018;
  • SpaceVM — a KVM hypervisor with its own management system, in the registry since December 2022;
  • Basis Dynamix — in the registry, with its own vCore hypervisor.

  Choosing between them is a separate task: compare cluster features, backup support and licensing terms.

• Hyper-V — if the infrastructure is already built on Windows Server and licenses are available.

How to migrate

1. Inventory. A list of VMs with resources, disks, networks (VLAN), service dependencies and downtime requirements.
2. Pilot. New platform on one or two servers, migration of several non-critical VMs, verification of performance and backups.
3. Drivers. In guest systems VMware Tools are replaced by drivers of the new platform; for Linux VMs on KVM these are the virtio drivers, for Windows — the virtio-win package, which is installed before migration.
4. Migrate in groups with a maintenance window and a rollback plan: the source VM is not deleted until the new one has run for the agreed period.
5. Configure backups on the new platform before migrating production systems, not after.

Typical mistakes

• Continuing to run an unsupported branch without a migration plan. Each month without updates increases the number of known vulnerabilities.
• Exposed ESXi and vCenter management interfaces on the Internet. They are regularly attacked; access should be only from the management network or via VPN.
• Migrating without checking drivers. Windows VMs without preinstalled virtio drivers will not boot from the disk on the new controller.
• Estimating costs by old price lists. Broadcom subscription terms differ from previous licenses; calculate based on the current offering taking the minimum core count into account.