What are Virtual Machines, Hypervisors, and Cloud Natives

Key Takeaways

• Virtual machines (VMs) allow you to run multiple operating systems on a single physical computer, like having several computers inside one.
• A hypervisor is the software boss that creates and manages these VMs, ensuring they don’t interfere with each other.
• Cloud-native approaches build apps designed from the ground up for cloud environments, emphasizing scalability and resilience using tools like containers.
• These technologies work together to power modern computing, from personal laptops to massive data centers, making resources more efficient and flexible.

We often hear terms like virtual machines, hypervisors, and cloud natives. These technologies have revolutionized how we use computers and build applications. But what do they actually mean? How do they work? And why are they so important? Lets Explore.

What Are Virtual Machines?

Imagine you have a single physical computer, but you need to run multiple operating systems on it. For example, you might want to use Windows for some applications and Linux for others. This is where virtual machines come in handy.

A virtual machine (VM) is like a computer inside your computer. It’s a software-based emulation of a physical computer that runs its own operating system and applications, just like a real computer. The virtual machine operates independently from the host computer, even though it shares the same physical hardware.

Think of it like having multiple apartments in a single building. Each apartment has its own rooms, furniture, and residents, but they all share the same foundation, plumbing, and electrical systems. Similarly, each VM has its own virtual hardware, operating system, and applications, but they all share the same physical computer.

How Virtual Machines Work

Virtual machines work through a process called virtualization. This process creates a virtual version of something, such as a computer system, storage device, or network resource.

Here’s a simplified breakdown of how VMs work:

1. The physical computer (called the host) runs special software that creates virtual environments.
2. Each virtual environment (called a guest) has its own virtual hardware, including CPU, memory, storage, and network interfaces.
3. The guest operating system and applications run on this virtual hardware, unaware that they’re not running on physical hardware.
4. The special software manages the allocation of physical resources to each virtual machine.

This setup allows multiple virtual machines to run on a single physical computer, each isolated from the others.

Types of Virtual Machines

Virtual machines come in different types, each suited for specific purposes:

System Virtual Machines

These are the most common type of VMs. They provide a complete system platform that supports the execution of a complete operating system.

Examples:

• Running Windows on a Mac computer
• Testing different operating systems without needing separate hardware
• Creating isolated environments for software development

Process Virtual Machines

These are designed to run a single process or application. They provide a platform-independent programming environment.

Examples:

• Java Virtual Machine (JVM) that allows Java programs to run on any device with JVM installed
• .NET Framework Common Language Runtime (CLR) that runs .NET applications

Benefits of Virtual Machines

Virtual machines offer numerous advantages:

• Resource Efficiency: Multiple VMs can run on a single physical machine, maximizing hardware utilization.
• Isolation: Each VM is isolated from others, so if one VM crashes or gets infected with malware, it doesn’t affect the others.
• Flexibility: You can run different operating systems and applications on the same hardware.
• Testing and Development: Developers can create test environments without needing additional hardware.
• Disaster Recovery: VMs can be easily backed up and restored, making disaster recovery simpler.

Drawbacks of Virtual Machines

Despite their benefits, VMs have some limitations:

• Performance Overhead: VMs require additional resources, which can lead to reduced performance compared to running directly on physical hardware.
• Resource Intensive: Each VM needs its own operating system, which consumes significant resources.
• Complexity: Managing multiple VMs can be complex, especially for large organizations.

Examples of Virtual Machines

Let’s look at some practical examples of how virtual machines are used:

Example 1: Software Development

A software developer needs to test their application on different operating systems. Instead of having multiple computers, they can create virtual machines on their single computer:

Physical Computer
├── VM 1: Windows 10
│   └── Application Testing Environment
├── VM 2: Ubuntu Linux
│   └── Application Testing Environment
└── VM 3: macOS
    └── Application Testing Environment

Example 2: Web Hosting

A web hosting company uses virtual machines to provide hosting services to multiple customers on a single physical server:

Physical Server
├── VM 1: Customer A's Website
├── VM 2: Customer B's Website
├── VM 3: Customer C's Website
└── VM 4: Customer D's Website

Each customer gets their own isolated environment with dedicated resources, ensuring that one customer’s activities don’t affect others.

What Is a Hypervisor?

Now that we know what virtual machines are, let’s explore the technology that makes them possible: the hypervisor.

A hypervisor is software that creates and runs virtual machines. It’s the bridge between the physical hardware and the virtual machines, managing how the physical resources are allocated to each VM.

Think of a hypervisor as a building manager in our apartment analogy. The building manager ensures that each apartment gets the right amount of electricity, water, and other resources, while keeping the apartments separate from each other.

How Hypervisors Work

Hypervisors work by abstracting the physical hardware and presenting it to virtual machines as virtual hardware. Here’s a simplified explanation of the process:

1. The hypervisor is installed on the physical hardware.
2. It creates virtual hardware environments for each virtual machine.
3. When a virtual machine needs to perform an operation (like saving a file or connecting to the internet), the hypervisor intercepts the request.
4. The hypervisor translates the request from the virtual environment to the physical hardware.
5. The physical hardware performs the operation.
6. The hypervisor returns the result to the virtual machine.

This process happens so quickly that the virtual machine and its operating system are unaware they’re running on virtual hardware.

Types of Hypervisors

There are two main types of hypervisors:

Type 1 Hypervisors (Bare-Metal)

Type 1 hypervisors are installed directly on the physical hardware, like an operating system. They have direct access to the hardware, which makes them more efficient and secure.

Examples:

• VMware ESXi
• Microsoft Hyper-V
• Xen
• KVM (Kernel-based Virtual Machine)

Type 2 Hypervisors (Hosted)

Type 2 hypervisors are installed as applications on an existing operating system. They rely on the host operating system to manage hardware resources.

Examples:

• VMware Workstation
• Oracle VirtualBox
• Parallels Desktop

Here’s a comparison of the two types:

Benefits of Hypervisors

Hypervisors offer several advantages:

• Hardware Independence: Virtual machines can run on any hardware that supports the hypervisor.
• Resource Optimization: Hypervisors efficiently allocate physical resources to virtual machines.
• Isolation: They provide strong isolation between virtual machines, enhancing security.
• Live Migration: Many hypervisors allow moving running virtual machines between physical hosts without downtime.
• Snapshotting: Hypervisors can capture the state of a virtual machine at a specific point in time, allowing for easy rollback.

Examples of Hypervisors

Let’s look at how hypervisors are used in practice:

Example 1: Data Center Consolidation

A company has 20 physical servers, each running a different application. By using a Type 1 hypervisor, they can consolidate these servers into just 5 physical machines, each running multiple virtual machines:

Before:
Server 1: Email Server
Server 2: Database Server
Server 3: Web Server
... (and so on for 20 servers)

After:
Physical Server 1 (with Type 1 Hypervisor)
├── VM 1: Email Server
├── VM 2: Database Server
├── VM 3: Web Server
└── VM 4: File Server

Physical Server 2 (with Type 1 Hypervisor)
├── VM 5: Application Server
├── VM 6: Development Server
├── VM 7: Testing Server
└── VM 8: Backup Server

... (and so on for 5 physical servers)

Example 2: Software Testing

A software tester needs to test an application on different operating systems. They use a Type 2 hypervisor on their computer:

Computer with Windows 10 (Host)
├── VirtualBox (Type 2 Hypervisor)
│   ├── VM 1: Ubuntu Linux
│   ├── VM 2: Windows 7
│   └── VM 3: macOS

This allows the tester to switch between different operating systems without needing multiple computers.

What Are Cloud Natives?

As we move from traditional computing to cloud computing, a new approach to building and running applications has emerged: cloud-native.

Cloud-native refers to applications designed specifically to run in a cloud environment. These applications are built to take advantage of the cloud’s scalability, resilience, and flexibility.

Think of it like the difference between a house built on a solid foundation and a mobile home. A traditional application is like a house built on a solid foundation – it’s stable but not easily moved. A cloud-native application is like a mobile home – it’s designed to be moved, scaled, and adapted as needed.

Principles of Cloud-Native Applications

Cloud-native applications are built on several key principles:

Microservices Architecture

Instead of building a single, monolithic application, cloud-native applications are broken down into smaller, independent services called microservices. Each microservice handles a specific function and can be developed, deployed, and scaled independently.

Example:
Instead of one large e-commerce application, you might have:

• User Service (handles user accounts and authentication)
• Product Service (manages product information)
• Order Service (processes orders)
• Payment Service (handles payments)

Containerization

Cloud-native applications are often packaged in containers, which are lightweight, standalone units that include everything needed to run the application, including code, runtime, system tools, and libraries.

Containers are similar to virtual machines but more lightweight. While VMs virtualize the entire hardware stack, containers virtualize the operating system, allowing multiple containers to share the same OS kernel.

DevOps Practices

Cloud-native development embraces DevOps practices, which combine software development (Dev) and IT operations (Ops) to shorten the development lifecycle and provide continuous delivery with high software quality.

Continuous Delivery

Cloud-native applications are designed for continuous delivery, allowing code changes to be automatically built, tested, and prepared for release to production.

Cloud-Native Technologies

Several technologies have emerged to support cloud-native development:

Containers

Containers are a fundamental technology for cloud-native applications. They provide a consistent environment for applications to run from development to production.

Popular container technologies:

• Docker
• rkt
• LXC (Linux Containers)

Kubernetes

Kubernetes is an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications. It’s become the de facto standard for container orchestration.

Serverless Computing

Serverless computing allows developers to build and run applications without thinking about servers. Developers write functions that respond to events, and the cloud provider handles all the infrastructure management.

Examples:

• AWS Lambda
• Azure Functions
• Google Cloud Functions

Benefits of Cloud-Native Applications

Cloud-native applications offer several advantages:

• Scalability: They can scale up or down automatically based on demand.
• Resilience: They’re designed to handle failures gracefully.
• Faster Development: Smaller, independent services allow for faster development and deployment.
• Resource Efficiency: They use resources more efficiently than traditional applications.
• Portability: They can run on any cloud platform or on-premises infrastructure.

Real-World Examples of Cloud-Native Applications

Let’s look at some practical examples of cloud-native applications:

Example 1: E-commerce Platform

An e-commerce company builds its platform using a cloud-native approach:

Cloud-Native E-commerce Platform
├── User Service (Container)
├── Product Service (Container)
├── Order Service (Container)
├── Payment Service (Container)
├── Search Service (Container)
└── Recommendation Service (Serverless Function)

Each service can be scaled independently based on demand. For example, during a sale, the Order Service and Payment Service might need to scale up, while the User Service remains stable.

Example 2: Media Streaming Service

A media streaming service uses a cloud-native architecture:

Cloud-Native Media Streaming Service
├── User Authentication Service (Container)
├── Content Management Service (Container)
├── Video Processing Service (Container)
├── Recommendation Engine (Serverless Function)
└── Analytics Service (Container)

When a new video is uploaded, the Video Processing Service automatically scales up to process it, and the Recommendation Engine updates its suggestions based on user viewing patterns.

How Virtual Machines, Hypervisors, and Cloud Natives Work Together

Now that we’ve explored each concept individually, let’s understand how virtual machines, hypervisors, and cloud natives work together to create modern computing environments.

At a high level, the relationship looks like this:

Physical Hardware
├── Hypervisor
│   ├── Virtual Machine 1
│   │   └── Cloud-Native Application
│   ├── Virtual Machine 2
│   │   └── Cloud-Native Application
│   └── Virtual Machine 3
│       └── Traditional Application

In this setup:

• The hypervisor manages the physical hardware.
• The virtual machines run on top of the hypervisor.
• Cloud-native applications run inside the virtual machines (or directly on containers managed by the hypervisor).

Evolution of Computing Environments

To better understand this relationship, let’s look at how computing environments have evolved:

Traditional Environment

In a traditional environment, applications run directly on physical hardware:

Physical Server 1
└── Application 1

Physical Server 2
└── Application 2

Physical Server 3
└── Application 3

This approach has several limitations:

• Poor resource utilization
• Difficult to scale
• Time-consuming to set up
• High maintenance costs

Virtualized Environment

With virtualization, we can run multiple applications on a single physical server:

Physical Server
├── Hypervisor
│   ├── Virtual Machine 1
│   │   └── Application 1
│   ├── Virtual Machine 2
│   │   └── Application 2
│   └── Virtual Machine 3
│       └── Application 3

This approach offers:

• Better resource utilization
• Easier scaling
• Faster setup
• Lower maintenance costs

Cloud-Native Environment

Cloud-native takes this a step further by using containers and microservices:

Physical Server
├── Hypervisor
│   ├── Virtual Machine 1
│   │   ├── Container 1 (Microservice 1)
│   │   ├── Container 2 (Microservice 2)
│   │   └── Container 3 (Microservice 3)
│   └── Virtual Machine 2
│       ├── Container 4 (Microservice 4)
│       ├── Container 5 (Microservice 5)
│       └── Container 6 (Microservice 6)

This approach provides:

• Even better resource utilization
• Automatic scaling
• Rapid deployment
• Lower maintenance costs
• Greater resilience

Use Cases and Examples

Let’s explore some real-world scenarios where these technologies work together:

Example 1: Global E-commerce Platform

A global e-commerce company uses a combination of virtual machines, hypervisors, and cloud-native technologies:

Data Centers Worldwide
├── North America Data Center
│   ├── Physical Servers
│   │   ├── Hypervisor
│   │   │   ├── VM 1: User Service (Cloud-Native)
│   │   │   ├── VM 2: Product Service (Cloud-Native)
│   │   │   └── VM 3: Order Service (Cloud-Native)
│   │   └── Hypervisor
│   │       ├── VM 4: Payment Service (Cloud-Native)
│   │       └── VM 5: Analytics Service (Cloud-Native)
├── Europe Data Center
│   └── (Similar setup)
└── Asia Data Center
    └── (Similar setup)

Each service is built using cloud-native principles, allowing it to scale independently based on regional demand. The hypervisor ensures efficient use of physical resources, while virtual machines provide isolation between services.

Example 2: Financial Services Company

A financial services company uses these technologies for its trading platform:

Trading Platform Infrastructure
├── Frontend Services
│   ├── Hypervisor
│   │   ├── VM 1: Web Application (Cloud-Native)
│   │   └── VM 2: Mobile API (Cloud-Native)
├── Backend Services
│   ├── Hypervisor
│   │   ├── VM 3: Trading Engine (Cloud-Native)
│   │   ├── VM 4: Risk Management (Cloud-Native)
│   │   └── VM 5: Data Processing (Cloud-Native)
└── Support Services
    ├── Hypervisor
    │   ├── VM 6: Authentication Service (Cloud-Native)
    │   ├── VM 7: Notification Service (Cloud-Native)
    │   └── VM 8: Reporting Service (Cloud-Native)

The trading engine needs to scale rapidly during market hours, while the reporting service might only need to scale at the end of the day. This architecture allows each service to scale independently based on its specific needs.

The Future

As we look to the future, these technologies will continue to evolve and work together:

• Edge Computing: Virtual machines and containers are moving closer to where data is generated, reducing latency.
• Hybrid Cloud: Organizations are using a mix of private clouds (using virtual machines and hypervisors) and public clouds (using cloud-native technologies).
• Serverless Virtualization: New approaches are emerging that combine the benefits of serverless computing with virtualization.
• AI-Optimized Infrastructure: Artificial intelligence is being used to optimize how virtual machines, hypervisors, and cloud-native applications work together.

WrapUP

In this article, we’ve explored three fundamental technologies that power modern computing: virtual machines, hypervisors, and cloud natives.

Virtual machines allow us to run multiple operating systems on a single physical computer, maximizing resource utilization and providing isolation between different environments.

Hypervisors are the software that makes virtualization possible, managing how physical resources are allocated to virtual machines.

Cloud natives represent a new approach to building and running applications, designed specifically for cloud environments with principles like microservices, containerization, and continuous delivery.

These technologies work together to create flexible, scalable, and resilient computing environments that power everything from small startups to global enterprises. As we continue to move toward an increasingly digital world, understanding these technologies becomes more important than ever.

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