A hypervisor—also known as a virtual machine monitor (VMM)—is a software layer that enables virtualization. It allows multiple virtual machines (VMs) to run on a single physical machine (host), each with its own operating system and applications.
In cloud computing, hypervisors are crucial because they help maximize hardware utilization, isolate workloads, and enable scalability—all key elements of cloud infrastructure.
A hypervisor is critical because it's the foundation of virtualization, which is what powers the cloud. Without it, the flexible, scalable, multi-tenant nature of cloud computing wouldn't be possible.
A single physical server can run multiple virtual machines (VMs).
This means better utilization of CPU, memory, and storage—no more idle hardware.
Each VM runs independently, with its own OS and applications.
If one VM crashes or is attacked, others stay unaffected—great for security.
Need more servers? Just spin up more VMs—no need to buy hardware.
Perfect for cloud services that need to scale on demand (like during high traffic).
Share physical resources across multiple tenants/customers.
Saves money on hardware, power, cooling, and space—especially for data centers.
Hypervisors make it fast and easy to create, configure, and clone new VMs.
That’s why cloud providers like AWS or Azure can let you launch a server in seconds.
You can take snapshots of VMs and restore them easily.
Helps with backup, recovery, and testing in case something goes wrong.
Want to run Linux on a Windows server? Hypervisors let you run different OSes on the same physical machine.
Hypervisors are what allow you and thousands of others to share physical infrastructure securely.
They power the virtual servers ("instances") you rent in the cloud.
A hypervisor works by creating and managing virtual machines (VMs) on a physical host machine. It acts as a virtual layer between the hardware and the operating systems, allowing multiple OSes to run simultaneously on a single physical server.
Let’s walk through it step by step:
The hypervisor splits up the host’s physical resources—like CPU, memory, disk, and network—into virtual components. It then assigns these to each virtual machine.
For example:
CPU → Virtual CPUs (vCPUs)
RAM → Allocated RAM per VM
Disk → Virtual hard drives
Network → Virtual network interfaces
Each VM thinks it's running on its own dedicated machine, but it’s actually sharing physical resources with others.
Each VM runs its own operating system and apps, completely isolated from other VMs. So:
One VM can run Linux
Another can run Windows
And neither knows the other exists
Even if one crashes, the others keep running—this is key for security and stability.
The hypervisor intercepts and manages low-level CPU instructions from the guest OS (inside the VM) and translates them to run on the host’s hardware.
It ensures:
Each VM gets fair access to resources.
No one VM hogs everything.
All VMs are sandboxed and protected.
The hypervisor monitors VM performance, allocates resources dynamically, and can pause, resume, clone, snapshot, or migrate VMs in real-time—great for DevOps and cloud automation.
Multiple virtual machines (VMs) run on one physical server.
Maximizes use of CPU, memory, and storage.
Reduces hardware waste and idle resources.
Each VM is isolated from the others.
One VM crashing won’t affect others.
Great for security, testing, and multi-tenant environments.
Easily spin up or delete VMs as needed.
Cloud providers can scale apps quickly without new hardware.
Ideal for elastic workloads and DevOps pipelines.
Virtual machines share resources, which can lead to slower performance compared to bare-metal (non-virtualized) setups.
Some apps (like high-performance databases or games) may not run as efficiently.
Multiple VMs competing for CPU, memory, or storage can cause bottlenecks, especially on underpowered servers.
One "greedy" VM can affect the performance of others if not managed properly.
Setting up, managing, and monitoring virtual environments requires technical skill and experience.
Troubleshooting issues can
