VMware ESXi

VMware ESXi
Name	VMware ESXi
Developer	VMware
Released	2001
Latest release version	8.0 U2
Latest release date	October 2023
Operating system	Hypervisor
Genre	Type 1 hypervisor
License	Proprietary

VMware ESXi. It is a bare-metal Type 1 hypervisor developed by VMware, a subsidiary of Dell Technologies. As a core component of the VMware vSphere platform, it enables the creation and management of virtual machines on physical servers, forming the foundation for modern data center and cloud computing infrastructure. Its compact, secure architecture allows it to be installed directly onto server hardware, abstracting CPU, memory, storage, and networking resources to run multiple operating systems concurrently.

Overview

Originally introduced as part of the ESX product line, it emerged as a streamlined, more secure successor, officially replacing its predecessor in the vSphere 5.0 release. The software is engineered for high efficiency, with a small footprint that runs directly from the host server's RAM, eliminating the need for a general-purpose operating system like Microsoft Windows or Linux. This design is central to VMware's strategy for server consolidation, business continuity, and building private cloud environments. It is widely deployed across industries, supporting critical applications from SAP and Oracle Database to custom workloads, and is a staple in enterprise IT environments managed by teams using tools like vCenter Server.

Architecture

The architecture is built around a proprietary kernel known as the VMkernel, which manages all hardware resources and schedules time on physical CPUs for virtual machines. It interfaces directly with server components from manufacturers like Dell EMC, Hewlett Packard Enterprise, and Cisco Systems, without an underlying operating system. Key components include the Direct Console User Interface for local management and support for PCIe devices via DirectPath I/O. The VMkernel provides resource management layers for CPU, memory, NFS, and Fibre Channel storage, enabling advanced features like vMotion and Distributed Resource Scheduler.

Features

It includes a robust set of features for enterprise virtualization. High availability is provided through vSphere HA, which restarts virtual machines on other hosts in a cluster after a hardware failure. vSphere vMotion enables the live migration of running virtual machines between physical servers with no downtime. For resource optimization, the Distributed Resource Scheduler automatically balances CPU and memory load across a cluster. Storage features include support for VMware Virtual SAN and integration with arrays from NetApp and IBM. Enhanced GPU support allows for workloads leveraging NVIDIA GRID technology.

Installation and configuration

Installation typically involves booting from an ISO image via DVD or USB flash drive onto compatible server hardware from vendors like Lenovo or Supermicro. The process uses an interactive text-based installer to configure the management network, assign a static IP address or use DHCP, and set a root password. Post-installation, basic configuration is done through the Direct Console User Interface, including configuring virtual switches for network connectivity to Cisco Nexus switches and defining datastores on iSCSI or Fibre Channel storage. The host is then usually added to a vCenter Server instance for centralized management.

Management

Primary management is performed through VMware vCenter Server, a centralized application that manages multiple hosts as a single entity. Administrators use the vSphere Client, a HTML5-based web interface, to perform tasks like creating virtual machines, configuring clusters, and applying vSphere Distributed Switch settings. PowerCLI, a command-line tool based on PowerShell, enables automation and scripting for large-scale deployments. Integration with other VMware products like vRealize Operations provides advanced monitoring, while vSphere Update Manager handles patching and compliance against baselines from the VMware Compatibility Guide.

Security

Security is a foundational principle, with features like a hardened VMkernel that has undergone evaluation by the National Security Agency. Secure Boot ensures the integrity of the hypervisor during startup, preventing the loading of unauthorized kernel modules. The Trusted Platform Module supports measured boot and virtual machine encryption. Role-based access control integrates with Active Directory for authentication, and logging can be forwarded to a syslog server like Splunk for audit purposes. Features like VM Encryption protect virtual machine data-at-rest, meeting compliance requirements for standards like PCI DSS.

Related products

It is the core hypervisor for the broader VMware vSphere suite. VMware vCenter Server provides centralized management for multiple hosts. VMware vSAN offers hyper-converged storage software that pools local disks. For public cloud extension, VMware Cloud on AWS leverages the software on Amazon Web Services bare-metal infrastructure. The NSX-T Data Center product provides network virtualization and security. Other related offerings include vRealize Suite for cloud management, vSphere Replication for disaster recovery, and Tanzu Kubernetes Grid for running containerized workloads managed by the Kubernetes orchestrator.

Category:VMware software Category:Hypervisors Category:Cloud computing