Containerization has been a significant development within the IT sphere since Docker was released in 2013 and was the first commercially successful containerization tool. We always hear people in IT saying, “well it works on my machine!”. But this doesn’t guarantee the app will work on others’ computers. And this is where containerization comes into play. Everyone in IT is always talking about containers and containerization because it can save time, money, and effort.
But what does it mean exactly? What does it do and what are its benefits? I’ll answer all these questions in this article. I’ll also show you how it works and the different types of containerization and services. Let’s get started!
What Is Containerization?
Containerization is where an application runs in a container isolated from the hardware. This container houses a separate environment specific to the application inside it. Everything the application needs to run is encapsulated and isolated inside of its container. For example, binaries, libraries, configuration files, and dependencies all live in containers. This means you don’t need to manually configure them on your machine to run the application.
Additionally, you don’t need to configure a container multiple times. When you run a containerized application on your local machine, it’ll run as expected. This makes your applications easily portable. As a result, you won’t worry whether the apps will run on other people’s machines.
But how exactly does this happen? Let’s jump into how containerization technology works.
How Does Containerization Technology Work?
Let’s break down the container’s layers.
Think of a containerized application as the top layer of a multi-tier cake. Now, we’ll work our way up from the bottom.
- Tier 1, the infrastructure. This includes CPUs, disk storage, network interfaces, etc.
- Tier 2, the host OS and kernel. This kernel is the bridge between the OS and the underlying system’s hardware.
- Tier 3, container engine and minimal guest OS. These are specific to the containerization technology in use.
- Tier 4, bin/lib and applications. This final layer includes each application’s binaries and libraries. It also has the applications running in their isolated user spaces.
To sum up, each container is an executable software package. This package also runs on top of a host OS. A host may even support many containers concurrently.
Sometimes, you may need thousands of containers. For example, this happens in the case of a complex microservices architecture. Generally, this architecture uses numerous containerized application delivery controllers (ADCs). This configuration works so well because the containers run fewer resource-isolated processes. And you can’t access these processes outside the container.
But why should you use containerization technology? Let’s look at its benefits.
What Are the Benefits of Containerization?
Containerization technology offers many benefits. One of which I mentioned earlier, is portability. You don’t need to worry if the application won’t run because the environment isn’t the same. You also can deliver containerized apps easily to users in a virtual workspace. But let’s take a look at 4 other benefits of containerization:
1. Cost Savings
Containerization cuts down on overhead costs. For example, organizations can reduce some of their server and licensing costs. Containers enable greater server efficiency and cost-effectiveness. In other words, you don’t need to buy and maintain physical hardware. Instead, you can run containers in the cloud or on VMs.
2. DevOps Support
Containerization offers more agility to the software development life cycle. It also enables DevOps teams to quickly spin up and spin down containers. In turn, this increases developer productivity and efficiency.
Encapsulation is another benefit. How so? Suppose one container fails or gets infected with a virus. All these problems won’t spread to the kernel nor to the other containers. That’s because each container is encapsulated. You can simply delete that instance and create a new one.
4. Kubernetes Support
Containers let you orchestrate them with Kubernetes. It’s possible to automate rollouts and rollbacks, orchestrate storage systems, perform load balancing, and restart any failing containers. Kubernetes is also compatible with other container tools. That’s why it is so popular! But you also can use other container orchestration tools, such as OpenShift, Docker Swarm, and Rancher.
Clearly then, containerization technology offers many, many benefits. But how does it differ from virtualization? Let’s find out!
What Is the Difference between Containerization and Virtualization?
Both VMs and containers provide an execution environment, but they’re still different. To simplify matters, I’ve created this table below.
|Deployment||Deploys multiple applications using the same OS on a single VM or physical server||Runs multiple VM with any OS on a single physical server|
|System Resources||Consumes fewer system resources of the host computer||Uses far more resources from the host system|
|Machine Capacity||Supports 100s to 1000s of containers on one machine||Supports 1-10 VMs on one machine|
Now, you know the difference between virtualization and containerization. But where can you use containers? And why should you use them? Let’s see.
What Services Are Containerized?
Besides applications, you also can containerize some services. This can facilitate their delivery in their containers. Let’s take a look at all the services that you can containerize.
This is a big one and perhaps the most used. Previously, software development used a monolithic code base. This meant including everything in one repo. But this method was hard to manage. Instead, it’s more efficient to break services (features or any data sent via third-party APIs) down into separate parts. After that, we can inject them into the application. Generally, separate development teams own these microservices, and they communicate with the main app via APIs.
Databases can be containerized to provide applications with a dedicated database. As a result, you won’t need to connect all apps to a monolithic database. This makes the connection to the database dedicated and easier to manage, all from within the container.
3. Web Servers
Web servers are quickly configurable and deployable with just a few commands on the CLI. It’s also better for development to separate the server from the host. And you can achieve that with the container. It’ll encapsulate the server.
You also can run containers within a VM (virtual machine). This helps maximize security, talk to selected services, or max out the physical hardware. It’s almost like a picture within a picture within another picture. Containerizing VMs lets you use the hardware to its maximum.
An application delivery controller manages an application’s performance and security. If you containerize ADCs, layer 4-7 services will become more available in DevOps environments. These services supply data storage, manipulation, and communication. This contributes to the overall efficiency of development.
Next, let’s take a look at some of the top containerization providers.
Top 4 Containerization Vendors
If you want to use containerization technology, you’ll need the help of a third-party solution. To this end, I’ve compiled this list of the top 4 vendors on the market. (Note: I classified these in alphabetical order, not from best to worst).
1. Amazon Elastic Container Registry (ECR)
ECR is an Amazon Web Services product that stores, manages, and deploys Docker images. These are managed clusters of Amazon EC2 (compute) instances. Amazon ECR also hosts images with high availability and scalable architecture. In turn, your team can easily deploy containers for your applications.
The pricing for AWS tools varies based on the number of tools you use and the subscription rates. Consult AWS for actual prices.
2. Apache Mesos
Mesos is an open-source cluster manager. Like Kubernetes, it manages the running containers. You also can integrate your own monitoring systems to keep an eye on your containers. Additionally, Mesos excels at running numerous clusters in large environments.
Mesos is an open-source tool.
3. Azure Kubernetes Service (AKS)
AKS is Microsoft Azure’s container orchestration service based on the open-source Kubernetes system. If your organization is using Azure, then you definitely need to use AKS. In fact, it easily integrates Kubernetes into Azure. Your development team can use AKS to deploy, scale, and manage Docker containers and container-based applications across a cluster of container hosts.
Azure services are also subscription-based. Consult Azure for the latest pricing for these services.
4. Google Kubernetes Engine
This Google container orchestration tool creates a managed, production-ready environment to deploy your applications. It facilitates the deployment, updating, and management of apps and services. This also gives you quick app development and iteration.
Google Cloud Services are also subscription-based. Consult Google for updated pricing.
These are some of the top vendors for containerization. But did you notice we’ve been talking a lot about Kubernetes and Docker? Let’s talk more about these tools and see why they go together like PB and J!
Kubernetes and Docker
The Docker Engine is perhaps the most well-known container tool worldwide. It’s the main component of container architecture. Additionally, Docker is a Linux kernel-based open-source tool. It’s responsible for creating containers inside an OS.
Kubernetes usually works together with Docker. It specifically orchestrates all the Docker containers running in various nodes and clusters. This provides maximum application availability.
Developers generally create containers from Docker images. Generally, these have a read-only status, but Docker creates a container by adding a read-write file system. It creates a network interface to allow communication between the container and a local host. Then, it adds an IP address and executes the indicated process.
Finally, let’s take a look at some of the options you have to get started using containers.
What to Consider When Selecting a Containerization Platform
You need to keep these 7 points in mind when shopping around for a containerization platform.
- Application architecture: Are your apps stateless or stateful? Are they monolithic, or do they use microservices? Ensure that the containerization platform meets all the architectural needs of your applications. Be mindful of the storage needs for stateful applications.
- Workflow and collaboration: What are some changes to the workflow? Will the platform enable collaboration with teams and stakeholders?
- DevOps: Did you switch to a DevOps way of working? What are the requirements for a self-service interface to deploy your apps by using a DevOps pipeline?
- Packaging: What formatting and tools are going to use the application code, dependencies, and containers? This is important to take into consideration to ensure a proper packaging fit.
- Monitoring and logging: Do the monitoring and logging options meet the requirements of the container platform? Do they work well within your development workflows? Ensure you have a proper plan in place for using the right infrastructure, application monitoring, and logging tools to collect a variety of metrics and data for analysis.
- Legacy application migration: Can the container platform support any legacy applications that may need to be migrated into the containers? This can be challenging, but it is doable in most cases. However, sometimes, you can’t do it, depending on the kind of application and how old it is.
- Application updates and rollback strategies: What’s your approach to updates and rollbacks? Work with your development team to define this.
These are some of the things to consider before selecting a vendor. Let’s wrap up!
The Bottom Line
To sum up, containerization offers many benefits. Primarily, it saves your IT operations money and time. It also makes IT jobs a lot easier. However, you should consider many things before picking the right tools.
Often, the best combination is Docker and Kubernetes. But depending on your environment, you might want to opt for AWS, Azure, Google, or open-source tools. I don’t recommend that only one person make this decision. Your development and DevOps teams need to come together and choose the best solution.
Do you have more questions? Are you looking for more information? Check out the FAQ and Resources sections below!
What is Docker?
Docker is a containerization tool released in 2013. It revolutionized how applications and services are handled virtually. Docker has also made it much easier for developers to port their applications to different systems and machines. That’s because Docker creates images of the application and environment. Then, it places them inside a container that can be on any machine.
What is Kubernetes?
Kubernetes is an open-source container orchestration tool. It helps manage and deploy applications on premises or in the cloud. Kubernetes also operates at the container level, not on the hardware level. It offers features such as deployment, scaling, and load balancing. It also allows you to integrate your own logging and monitoring.
What is Virtualization?
Virtualization lets you create a virtual machine or isolated environment. This helps you use environments to run more than one project on one machine. Isolating environments even stops variable conflicts between dependencies. It also allows for a cleaner, less buggy development process.
What is Containerization?
Containerization is a form of virtualization. But instead of running a VM, you can create many containers and run many applications in their own environments. Containerization lets you transfer programs between teams and developers. It also allows you to take advantage of your hardware by hosting many applications from one server. Additionally, you can run all kinds of environments on one server without conflicts.
What is network orchestration?
Network orchestration creates an abstraction between the administrator and cloud-based network solutions. Administrators can easily provision resources and infrastructure dynamically across multiple networks. Orchestration tools are very useful if you have multiple applications running in containers. The more containers you have, the harder it is to manage without the proper orchestration software.
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