If you’re looking to improve computer performance, the list narrows down to two notable inventions: virtualization and containerization. Both methods have allowed IT professionals to benefit from the physical hardware running on a server. The goal is to use the same resources but run different operating systems.
The question I’ll be answering in this article is: which one is right for you and your business needs? Most likely both. I’ll give you the rundown of what virtualization and containerization are. I’ll then discuss their pros and cons, how they work, and what the best options are. Now, let’s jump into defining virtualization in the following section.
What Is Virtualization?
Virtualization is the emulation of a computer within a computer. Virtualization and virtual machines (VM) go back to the 1960s. That said, they weren’t widely used until the early 2000s. You can’t help but wonder, what was the purpose that drove the industry towards virtualization and VMs? Simply put, business.
In the 1990s, many companies had only physical servers, data centers, and single-vendor tech stacks. This means the technology evolved and IT departments had to upgrade to new technology. Thus, businesses had to preserve their legacy applications and use servers that could only run one vendor-specific software. Partitioning servers to run legacy apps and using the rest of the server for running other applications was the start of the virtualization we know and love today. Companies partitioning servers also led to the development of virtual machines. Let’s talk about VMs next.
What Are Virtual Machines?
When people talk about virtualization, they’re talking about virtual machines. Virtual machines are emulated computers that run on physical servers. So, you get one server with many other computers running various operating systems. Running a virtual machine also allows you to maximize the utility of your server. You can also save on the cost of having physical machines for each VM. That said, and with modern tech, you can’t have a bunch of VMs running without software. You’ll need a hypervisor to monitor and run it.
What Is a Hypervisor?
A hypervisor is a software or firmware that allows multiple operating systems to run on the same physical server. The principal role of the hypervisor is to orchestrate and separate the physical server’s resources and deliver the resources to each VM to ensure peak performance. This means you can’t have virtualization on your server without a hypervisor. It’s an absolute must. Now, we have a hypervisor and a VM, but how does that work exactly? Let’s see.
How Does Virtualization Work?
Virtualization takes your physical computer and partitions it and its resources into separate computers. For example, let’s say you have one physical server and want to create four VMs. The hypervisor I mentioned earlier will partition, monitor, and control your physical resources for each one of your four VMs.
You can think of a VM as a single file. Like any file, you can move it around to different computers and work without issues. Then, you’re able to have users log into your VMs from their computers and then use that VM for work. Your VMs may also be servers, and your users log in to make changes. Anything is possible with a VM. That said, what if you want something lightweight and consumes fewer resources? Let’s take a look at containers.
Pros and Cons of Virtualization & VMs
As with anything, you’ll always find good and bad sides. Here, I’ll give you the top 5 pros and cons of using virtualization. Let’s start with the benefits, move on to the cons, and then in the next section, touch on the technology.
|Maximum hardware resources: get the most bang for your buck on your servers||Large capital investment to set up|
|High availability: VMs are always available||Stored data can be at risk|
|Easy recovery or rollbacks||Challenging scalability|
|Easy setup||Slower performance with more VMs on one server|
|Simple cloud migration||Server sprawl: having one server dedicated to one task|
What Is Containerization?
Containerization is where an application runs in a container isolated from the hardware. The hardware or server runs the container, but inside of the container, it runs a separate environment specific to the application. Everything the application needs to run is encapsulated and isolated. For example, binaries, libraries, configuration files, and dependencies live in the container. You also don’t need to manually configure them on the end user’s machine to run the application. In the case of the container, it’s just an environment and an application running, not a full-fledged VM. So how does that work?
How Does Containerization Work?
Each container is an executable software package that runs on top of a host OS. This host could be a VM or a physical computer. A host may support many containers concurrently. Sometimes you may have thousands of containers. One example is a complex microservices architecture that uses numerous containerized application delivery controllers (ADCs). This configuration works so well because the containers run fewer resource-isolated processes that you can’t access outside the container. Now, let’s look at the pros and cons of containerization.
Pros and Cons of Containerization
Like virtualization, containers have pros and cons too. Check the following table for the 4 pros and cons of containerization.
|Is lightweight, quick, isolated infrastructure||Works great in Linux, but not so much in other OS|
|Includes its operating environment inside||Has kernel vulnerability that affects all containers|
|Is usually less than 100Mb||May face networking issues while keeping containers isolated|
|Decreases ops costs||Has monitoring container that’s harder than a VM|
Virtualization vs Containerization
In this section, I’ll break down the differences and similarities between virtualization and containerization.
In the table below, I compare the top 7 criteria for virtualization and containerization technologies.
|Isolation||Has complete isolation from host and other VMs||Has isolated from the host but not as strong a security boundary as a VM|
|OS||Has complete OS with kernel, requires more host resources||Runs a portion of the OS and can be configured to have more or less|
|Guest Compatibility||Can run any OS in the VM||Runs the same OS and version as the host|
|Deployment||Deploy VMs with a hypervisor||Deploy containers with Docker and manage with an orchestrator like Kubernetes|
|Persistent Storage||Has Virtual Hard Disk or shared storage between VMs with Server Message Block||Has local disk|
|Load Balancing||Run VMs in other servers as a failover to perform VM load balancing||Has orchestrator that starts or stops containers based on load and availability|
|Networking||Has virtual network adapters||Has isolated virtual network adapter|
After you’ve digested this information, the following section will show you how to use your containers and VMs together.
Containers and Virtual Machines: Can You Use Them Together?
You can use both technologies together in any way you want. They’re interoperable and you can run containers inside a VM. It also makes sense to do this since you can further increase your servers’ efficiency. The ability to mix and match containers with traditional VMs can be a deciding factor for many developers and operational teams. That’s especially when choosing a cloud hosting provider for their projects. Using both allows you to lower operating costs and increase your ROI over time.
Which Option Is Best for You?
If you’re still not sure which is a better technology for your needs, then read through the following points to help get a better understanding of when to use each technology.
- Manage more than one OS
- Manage more than one application on one server
- Run an app that requires all the resources and functionalities of an OS
- Ensure full security and encapsulation
- Run the max number of apps on one server
- Deploy more than one instance of a single app
- Start the system instantly thanks to lightweight technology
- Develop an app on the host infrastructure
Virtualization and containerization are both vital inventions for improving your computer performance. In this article, you’ve learned what virtualization and containerization are, how the technology works, and what makes them different and similar. You’ve also learned what you need to know about choosing between the two technologies based on your technical needs. In any case, it’s safe to say that in today’s modern IT environment, you’ll need to have one, and in many cases both, to get the maximum out of your physical hardware.
Have more questions? Check out the FAQ and Resources below!
What is Docker?
Docker is a containerization tool released in 2013. It revolutionized the virtual handling of applications and services. Docker has made it so much easier for developers to port their applications to different systems and machines. That’s because Docker creates images of the application and environment and places them inside a container you can run on any machine.
What is Kubernetes?
Kubernetes is an open-source container orchestration tool. This allows for the management and deployment of applications in the cloud or on-premise. Kubernetes operates at the container level and not on the hardware level. It offers features such as deployment, scaling, and load balancing and allows you to integrate your own logging and monitoring.
What is virtualization?
Virtualization is a virtual machine or isolated environment where you can create other environments. It allows you to run more than one project on one machine. Isolating environments stops variable conflicts between dependencies and allows for a cleaner, less buggy development process.
What is containerization?
Containerization is a form of virtualization. That said, instead of running a VM, you can create many containers and run many applications with specific environments. This makes it easy to transfer programs between teams and developers. It also hosts many applications from one server to allow you to benefit from your hardware. Due to the contained nature of environments, you can run them all on one server without conflicts.
Does virtualization affect performance?
Yes, it does. That said, it all depends on what you’re doing with that VM. It also depends on the availability of the remaining system resources on your host server. If you’re looking to save on resource consumption, you might choose VMs based on Linux. This is because it uses fewer system resources than Microsoft or Apple.
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