Containerization vs. Virtualization: What's the Difference?
If you’re looking to improve scalability, reduce overhead costs, and standardize software deployments across multiple machines and platforms, containers and virtual machines (VMs) are two of the top approaches in use today. They’re not mutually exclusive, either—both can help your IT team become more agile and responsive to business demands. However, the concepts can be confusing.
Both containers and virtual machines (VMs) are software technologies that create self-contained virtual packages. Beyond that commonality, they differ in their operations, characteristics and use cases.
So, to distinguish between containers and VMs, we’ve rounded up the basics on each.
What are virtual machines and virtualization?
Before containers came along, the “virtual machine” was the technology of choice for optimizing server capacity. Programmed to emulate the hardware of a physical computer with a complete operating system, VMs (and hypervisors) make it possible to run what appear to be multiple computers with multiple different operating systems on the hardware of a single physical server.
What is a hypervisor?
Virtualization is not possible without the hypervisor. A hypervisor, or virtual machine monitor, is the software or firmware layer that enables multiple operating systems to run side-by-side, all with access to the same physical server resources. The hypervisor orchestrates and separates the available resources (computing power, memory, storage, etc.), aligning a portion to each virtual machine as needed.
What are the advantages and disadvantages of virtual machines?
Visually, each virtual machine image looks like a data folder. Each can be moved and copied as easily as you can move and copy other kinds of files. In this way, your team can centralize workloads and run several different operating systems without increasing overhead, a huge advantage over on-premises hardware. You can also update apps and the OS without affecting the end-user experience.
However, virtual machines are not without their disadvantages:
Since each VM includes an OS and a virtual copy of all the hardware the OS requires, VMs require significant RAM and CPU resources
Due to the increase in virtual copies and required resources, the software development life cycle is more complex with VMs
Moving VMs between public clouds, private clouds and traditional data centers can be challenging
What are containers and containerization?
“Where shipping containers hold products comprising many different parts, a software container encapsulates an application—often a single executable service or microservice—along with its libraries, frameworks and other components. ”
Just as the use of shipping containers transformed global logistics, the rise of the software container is transforming software development and deployment.
The container shares the kernel of the host OS with other containers, and the shared part of the OS is read-only. Therefore, the containers are lightweight, so you can deploy multiple containers on a single server (or a VM)—no more dedicating an entire server to a single application. And, you only have one OS to maintain. Scaling up becomes fast and easy, without the need for more server space.
Containerization solves any number of problems for software development and deployment.
In fact, that’s why we adopted the concept ourselves in migrating our managed services portal to Google Cloud.
But, as with virtual machines, containers have their disadvantages:
All containers on a particular host machine must be designed to run on the same kind of OS. Containers based on a different OS will require a different host.
Because the OS is shared, a security vulnerability in the OS kernel is a threat to all containers on the host machine.
Containerization is still a new solution with wide variances in implementation plans and skilled resources, making adoption a challenging process for some
Containerization or virtualization: What’s the right path for you?
Virtualization enables you to run multiple operating systems on the hardware of a single physical server, while containerization enables you to deploy multiple applications using the same operating system on a single virtual machine or server.
Virtual machines are great for supporting applications that require an operating system’s full functionality when you want to deploy multiple applications on a server, or when you have a wide variety of operating systems to manage. Containers are a better choice when your biggest priority is to minimize the number of servers you’re using for multiple applications.
Your use case matters too. Containers are an excellent choice for tasks with a much shorter lifecycle. With their fast set up time, they are suitable for tasks that may only take a few hours. Virtual machines have a longer lifecycle than containers, and are best used for longer periods of time.
The way forward for your organization will depend on everything from the size of your operations and workflows to your IT culture and skill sets. And, containerization and virtualization technologies are coming together in some interesting new ways that could influence your decision making.
Ultimately, virtualization and containerization may both have a place in your IT strategy. Consider your ultimate goals, immediate use cases, and team skillset before setting down a specific path. At Burwood Group, we recently leveraged containerization to run our own client-facing managed services portal: read about the project scope and outcomes here.
