Virtualization is a vital tool in the IT world, enabling companies to optimize their hardware resources and improve the efficiency and management of their systems. VMware ESXi has been an undisputed leader in this space, but with its purchase by Broadcom and the very important changes in pricing, and above all, the elimination of its free version, thousands of customers are evaluating the existing alternatives.
Here is our small contribution, as IBM PowerVM experts but also enthusiasts of the other KVM-based options. All of them (except VMWare) work in our labs and depending on the projects we choose one or the other for our customers. If you would like us to discuss it in detail
please contact us without obligation.
While it is difficult to provide a comprehensive comparison with all ESXi features, as they vary between versions and specific combinations with other VMware tools, the following table provides a summary of what we consider to be the most important ESXi features and how they are supported in LXD, PowerVM, Proxmox and Red Hat OpenShift. We hope you find it useful.
| Feature | LXD | VMware ESXi | PowerVM | Proxmox | Red Hat OpenShift (OCP)* |
|---|---|---|---|---|---|
| Type of software | Open source. | Owner | Proprietary (IBM specific) | Open source (KVM and container-based) | Proprietary (based on Kubernetes and containers) |
| It is based on | KVM. Just as OCP supports containers and also VMs. | VMkernel | Based on IBM technology inherited from Mainframe environments, with advanced processor micro-partitioning technologies and HW isolation of VMs. | KVM and LXC | KVM (for virtual machines *if installed in bare-metal mode and not on top of other hypervisors) and Kubernetes for containers |
| Web UI | Yes | Yes, but limited. vSphere is required for many functionalities. | Yes HMC (equivalent to vSphere) or PowerVC (based on OpenStack) | Yes | Yes |
| Clustering | Yes | Yes | Yes | Yes | Yes (through Kubernetes) |
| High Availability | Yes | Yes | Yes | Yes | Yes (with advanced Kubernetes features) |
| VM live migration | Yes | Yes | Yes | Yes | Yes (via Kubernetes and OpenShift Virtualization) |
| Shared storage | Ceph | vSAN | Supports various file systems and storage | Ceph, ZFS and others | GlusterFS, Ceph and others |
| Networking | Bridge, OVN | NSX | Compatible with almost all network technologies | Bridge, VLAN, VXLAN and others | SDN, OVN and others |
| Snapshots | Yes | Yes | Yes | Yes | Yes |
| Backup | Yes | Yes | Yes (with IBM and third-party management tools) | Yes | Yes |
| Free trial | N/A (unlimited free use) | 30 days | Not applicable (included free with IBM hardware) | N/A (unlimited free use) | Free trial available |
| Cost | Free of charge, with enterprise support available per physical host | Full functionality requires a paid license. | Included with IBM Power hardware | Free of charge, with enterprise support by subscription | Core-based underwriting; varies by environment. |
| Number of yarns | Limited to 2 threads per core (x86) | Limited to 2 threads per core (x86) | Up to 1,920 threads (Power10 E1080) | Limited to 2 threads per core (x86) | Limited to 2 threads per core (x86) |
| Type of hypervisor | Level 1 (over KVM) | Level 1 | Level 0 (separate VMs at firmware level with CPU mapping) | Level 1 (KVM) and Level 2 (LXC) | Level 2 (on RHEL) |
| Technology maturity (years) | > 10 years | > 20 years | > 30 years (coming from Z environments / LPARs) | > 10 years | > 10 years |
| Maximum RAM capacity per VM | Up to 2TB | Up to 2 TB | Up to 32 TB | Up to 2TB | Up to 2TB |