Open-source VMware vSphere alternatives

KubeVirt is an add-on that brings virtual machine management to Kubernetes. Its aim is to give virtualization solutions a shared foundation on top of Kubernetes, so that workloads that need a full virtual machine can run in the same cluster as containers.

KubeVirt extends Kubernetes by adding virtualization resource types, especially the VM type, through Custom Resource Definitions. This lets the Kubernetes API manage VMs alongside all other resources. That functionality does not go into Kubernetes itself; instead KubeVirt supplies extra controllers and agents that run on an existing cluster. Through these, a VM can be declaratively created from a predefined definition, scheduled onto the cluster, launched, stopped and deleted.

KubeVirt is written in Go and licensed under Apache-2.0. The project provides a quickstart, user documentation, a blog, a YouTube channel and developer documentation covering architecture, components and the API reference.

Incus manages system containers and virtual machines. It gives a single, unified way to run and manage full Linux systems inside either, with images for many Linux distributions, including official Ubuntu images and community-provided ones.

It is built around a REST API and runs anywhere from a lone instance on one host to a cluster that fills a data center rack, so it can serve both development and production workloads. The README describes it as a way to set up something that feels like a small private cloud, and suggests it for people who want to containerize different environments, run virtual machines or manage infrastructure cost-effectively. A try-it page lets you test Incus online.

Incus began as a community fork of LXD, made after Canonical took over that project from the Linux Containers community, and it is maintained by the same developers who first created LXD. It is written in Go, has no contributor license agreement and remains under the Apache 2.0 licence.

Harvester is a hyperconverged infrastructure (HCI) platform built on Kubernetes. It runs on bare-metal servers and combines virtualization with distributed storage, giving operators a cloud-native alternative to traditional virtualization stacks that relies on direct-attached local storage instead of complex external SANs.

Harvester ships as a bootable appliance image that can be installed from an ISO or automatically through iPXE scripts. Virtual machines can be created, edited, cloned and deleted with SSH key injection, cloud-init and console access, moved between hosts with live migration, and backed up to NFS, S3 or NAS targets for later restore. Storage management covers distributed block storage and tiering, and networking supports virtual IPs and multiple network cards.

Because it uses the Kubernetes API as a common automation layer for container and VM workloads, and integrates with Rancher to support containerized environments, it can unify older virtualized infrastructure with container adoption from core to edge locations. Harvester is written in Go and licensed under Apache-2.0.

LXD manages full Linux systems running inside system containers or virtual machines, giving a unified way to run and manage both. It supports images for many Linux distributions, including official Ubuntu images and community-provided ones, and is built around a REST API.

It scales from a single instance on one machine to a cluster spanning a data center rack, so it is used for both development and production workloads. The result is something that feels like a small private cloud, where different workloads can run efficiently while resource use stays optimized. The README suggests it for containerizing separate environments, running VMs, and managing infrastructure cost-effectively.

The LXD daemon runs only on Linux, but the lxc client tool is available on most platforms, installable through Snap, Chocolatey or Homebrew. LXD is written in Go, maintained by Canonical and licensed under AGPL-3.0, with documentation and release announcements published online.

Apache CloudStack is open source software for deploying and managing large networks of virtual machines as a highly available, scalable infrastructure-as-a-service cloud. Service providers use it to offer public cloud services, while companies use it for private on-premises clouds or as part of a hybrid setup. It is written mainly in Java and Python.

The project describes it as a turnkey solution that includes the full stack most organizations want from an IaaS cloud: compute orchestration, network-as-a-service, user and account management, resource accounting, a complete native API and a user interface. Administrators can manage the cloud through a web interface, command-line tools or a query-based API.

CloudStack supports a range of hypervisors, including VMware vSphere, KVM, XenServer, XenProject and Hyper-V, as well as OVM and LXC containers. Topics also mention Kubernetes, XCP-ng and libvirt. It is an Apache Software Foundation project licensed under Apache-2.0, with documentation, a demo, news and events pages and security reporting procedures on its website.

libvirt is an open-source virtualization management library written in C and released under the LGPL-2.1. It provides a common API and tooling layer for managing virtual machines and containers across different hypervisors and technologies, so that management software does not have to speak each platform's own interface.

Other projects build on it, for example the virt-manager desktop tool, which manages QEMU/KVM, Xen and LXC through libvirt drivers. Administrators and tool authors use libvirt to create, configure, start and stop guests and to manage their storage and networks, usually through command-line tools or bindings for other languages.

The GitHub repository is a read-only mirror. Merge requests and issues go to the project's GitLab instance, where development takes place, so the GitHub copy is mainly useful for browsing the source.

ProxCenter is a web-based management console for Proxmox Virtual Environment. It brings several Proxmox VE clusters and Proxmox Backup Server instances into one interface, and the project positions it as an alternative to VMware vCenter for people who run Proxmox but want centralized control across clusters.

The community feature set includes multi-cluster inventory and topology views covering nodes, guests, storage, networks and the Ceph CRUSH tree, in-browser consoles using noVNC and SPICE, backup and replication visibility, and role-based access control with single sign-on. It can also migrate virtual machines from VMware, Hyper-V, Nutanix and XCP-ng, including warm migration. Enterprise features add DRS-style workload balancing, alerts and reports, an MSP mode and high availability.

The application is written in TypeScript and installed on your own server with a script that sets up Docker, a Compose stack and PostgreSQL, after which you create the first admin account. A live demo and documentation are available. The project is split into Community and Enterprise tiers, and it suits sysadmins and managed service providers running Proxmox at scale.