I'm building my virtualization skills and deciding whether to prioritize VMware ESXi or focus on alternatives such as Proxmox, KVM, or Hyper-V. With VMware's licensing changes and many organizations reconsidering their VMware deployments, I'm unsure how valuable ESXi will remain for someone starting out.
For hands-on practice, I can't wipe a spare physical server. I'm considering installing VMware Workstation Pro on the existing operating system of an unused company server, then running ESXi as a nested hypervisor. What performance and networking issues should I expect? How can I isolate the lab so its virtual DHCP, broadcasts, and test traffic cannot affect the host or production network? I'd also appreciate advice on the virtualization concepts to learn first and recommendations for reliable learning resources.
5 Answers
ESXi is still useful if you’re targeting an employer that runs VMware, since plenty of organizations still have it in production. However, the direction of the market is mixed: licensing costs have pushed many teams toward Proxmox, KVM, Hyper-V, Nutanix, or other products. I’d learn the basics on an accessible platform such as Proxmox or KVM, then spend enough time with ESXi to understand its terminology and management model.
I’d start with Proxmox or Hyper-V for a home lab because they’re easier to obtain and practice with, then add ESXi if a particular job requires it. A Windows machine can run Hyper-V, and a capable system can host nested Proxmox or ESXi. Documentation from the relevant Linux distribution or vendor is often more useful than relying exclusively on videos.
The safest long-term investment is learning virtualization fundamentals rather than tying yourself to one vendor. Understand CPU and memory allocation, virtual disks and storage backends, vNICs, virtual switches, VLANs, bridging, clustering, quorum, high availability, backups, and live migration. Those concepts transfer between ESXi, Proxmox, KVM, Hyper-V, and other platforms.
Knowing how to provision and reallocate resources, design clusters, and troubleshoot networking or shared storage will also make it much easier to move between platforms—or help with a VMware migration.
For a nested lab, enable hardware-assisted virtualization and expose it to the guest hypervisor. Expect reduced performance, especially with storage-heavy workloads, and remember that nested networking may not behave exactly like physical networking. Use a dedicated fast SSD or NVMe location if possible, keep the lab resource limits conservative, and avoid running demanding workloads on the shared host.
Put the lab behind an isolated virtual switch or host-only network with no connection to the physical adapter. If the lab needs internet access, use controlled NAT through the host rather than bridging it directly to the company network, and make sure only one intentionally configured device provides DHCP.
There’s no harm in learning several hypervisors. VMware remains common enough to recognize, but specializing only in ESXi is riskier than it used to be. Build a small lab where you practice creating VMs, changing resource allocations, configuring virtual networking, attaching storage, taking backups, and recovering or migrating workloads across platforms.
Some smaller organizations and higher-education environments still run a handful of ESXi hosts, so it hasn’t disappeared. The best choice depends on the jobs you’re applying for.