Hypervisor

A hypervisor (virtual machine monitor) is specialized software, firmware or a hardware scheme that creates and manages virtual machines (VMs), providing each of them with an isolated environment with its own virtual hardware resources — a processor (vCPU), RAM (vRAM), disks (vDisk) and network interfaces (vNIC). The hypervisor is a key component of any virtualization platform and acts as an arbiter between the physical resources of the server and the virtual machines running on it. It is the hypervisor that allows running several operating systems simultaneously on one physical host (Windows, Linux, Astra Linux), completely isolated from each other — each VM has no access to the memory, data or processes of neighboring VMs. Hypervisor technology underlies modern data centers and cloud platforms (IaaS), ensuring maximum equipment utilization, flexible management of computing resources and high service availability. It should be noted that the hypervisor is exactly the software that implements the virtualization technology at the software level.

Types of hypervisors and their comparison

There are two main types of hypervisors. Type 1 hypervisors (bare-metal, native) are installed directly on the server hardware, without a base operating system. They interact with hardware resources directly, which ensures maximum performance (minimal overhead — usually less than 5%), stability and security. Examples are VMware ESXi, Microsoft Hyper-V Server, Proxmox VE (based on KVM), XenServer, Nutanix AHV, as well as Russian developments included in the register of domestic software. Type 1 hypervisors are the standard for server virtualization in corporate data centers. Type 2 hypervisors (hosted) run on top of an existing operating system (Windows, Linux, macOS) as a regular user-mode application. They have additional overhead due to the host OS layer and are used mainly for testing, development and personal computers: Oracle VirtualBox, VMware Workstation/Fusion, Parallels Desktop, QEMU (without KVM). For corporate use, Type 2 hypervisors are poorly suited, since their performance is lower, and a failure or compromise of the host OS leads to the shutdown of all VMs.

Key functions and capabilities of a modern hypervisor

A modern hypervisor performs a wide range of critically important functions. Resource management: the hypervisor dynamically distributes physical resources (CPU, memory, disk, network) between virtual machines, using scheduling and load balancing mechanisms. It can guarantee a minimum level of resources (reservation), set limits and manage access priorities (shares). Isolation: the hypervisor guarantees complete isolation of virtual machines at the hardware level — no VM has access to the memory, data or devices of a neighboring VM. This is critically important for multi-tenant environments and security requirements. Migration: support for live migration (vMotion) — moving a running virtual machine from one physical host to another without stopping services, with zero downtime. Storage vMotion allows moving VM disks between storage systems without stopping. High Availability (HA): in case of a physical server failure, the hypervisor automatically restarts virtual machines on healthy cluster hosts within minutes. Fault Tolerance (FT): creating and maintaining a synchronous copy of a VM on another host to ensure zero downtime in case of failure. Snapshots: creating instant snapshots of the VM state (disks + memory) for quick rollback to a previous state, which is indispensable when testing updates. Templates: creating standard VM images for rapid replication of similar servers.

Choosing a hypervisor for an enterprise and import substitution

When choosing a virtualization platform, it is necessary to take into account compatibility with hardware (HCL — Hardware Compatibility List), performance and fault tolerance requirements, the cost of licensing and subscription, the availability of technical support, as well as the requirements of regulators for the software used. For Russian state customers and CII facilities, the use of hypervisors from the register of Russian software is mandatory. The specialists of the Fintech company help select the optimal virtualization platform, design a cluster architecture, perform installation and configuration of the hypervisor, as well as migrate existing virtual machines from foreign platforms to domestic ones. A competent choice of a hypervisor is the basis of a stable, productive and secure IT infrastructure of an enterprise. When switching to domestic solutions, the Fintech company provides full support: auditing the current infrastructure, developing a migration plan (P2V, V2V), testing application compatibility, training administrators and support at all stages of the project.