A hypervisor is software, firmware or hardware-assisted technology that creates, runs and isolates virtual machines on a physical host by allocating CPU, memory and devices to each guest.
Why it matters
The hypervisor is the layer that makes virtualization work and the foundation of most cloud infrastructure. Its quality affects security, since it enforces isolation between tenants, and performance, since it schedules guests onto physical CPUs.
Type 1 hypervisors run directly on hardware, such as KVM, Xen and VMware ESXi. Type 2 hypervisors run as an application inside a normal operating system, such as VirtualBox on a laptop.
Example
On a Linux server with KVM, you can define a guest with 2 vCPUs and 4 GB RAM. The hypervisor maps those to real cores and memory, and presents the guest with a virtual network card and disk.
Common mistakes
- Assuming a type 2 hypervisor is suitable for production servers.
- Forgetting to patch the hypervisor; a flaw there can affect every guest.
- Disabling hardware virtualization support in the firmware, which makes guests very slow.
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यह पेज सामान्य जानकारी है, जिसे हमारी संपादकीय टीम ने लिखा है और दस्तावेज़ीकरण बदलने पर अपडेट किया जाता है। सर्वर और प्रदाता अलग-अलग होते हैं, इसलिए बदलाव पहले सुरक्षित तरीके से जाँचें। देखें: संपादकीय नीति और अस्वीकरण.