It’s no secret that containers have taken the cloud computing world by storm. The technology has been widely adopted by enterprises of all sizes and has become the preferred way to package and deploy applications.
So, what exactly are containers and how do they work? In simple terms, a container is a self-contained unit of software that includes everything needed to run an application: the code, runtime, system tools, and libraries.
Containers are isolated from each other and can be run on any server, making them ideal for cloud computing. This blog explains everything you need to know about containers, including their benefits and how they work. You will also learn the difference between Virtual Machines and containers.
Stay tuned till the end to learn the best!
What are Containers?
Containers are software packages that contain an App along with all the other dependencies such as binaries and libraries for the contained app to run. As mentioned earlier, they are a self-contained unit of software.
Note that multiple apps can run in a single container although we do not make use of it. You can assume that one container means one app.
The following are the key features of the containers in cloud computing:
- Containers run on a container engine such as Docker engine, which is the most popular one.
- This container engine runs on a host Operating System such as Linux on the hardware.
- Since containers are small in size, light-weight and include only the dependencies, they do not need to run an OS in each container. Virtual Machines, on the other hands, do need OSs.
- The major difference between VMs and containers is that VMs run an OS in each VM, whereas containers don’t.
- Due to this major difference, there is a huge difference in the costs and benefits of containers and VMs.
- A software platform that automates the deployment, management and scaling, etc. of the containers is called a Container Orchestration.
- For example, you must have heard about Kubernetes, which is the most popular container orchestrator. Docker also has one container orchestrator called Docker Swarm.
What’s the Need for Container Orchestrator?
In small numbers, manual operation of containers is possible. However, when it comes to large-scale systems such as involving Microservices, we may require thousands of containers. That many containers cannot be managed manually in real-time.
So, instead of one app, you might have hundreds of different microservices running together to form the larger solution.
Note: Microservices architecture is an approach to software architecture that divides a larger solution into smaller parts (microservices). These microservices run in containers that can be orchestrated by Kubernetes or another platform.
What’s the Difference between Containers and Virtual Machines?
Virtual Machines (VMs)
Each VM runs its own OS. Therefore, it can take minutes to boot up.
Containers can boot up in milliseconds.
VMs occupy more space in gigabytes in the disk.
Containers do not take much disck space. They take space in megabytes.
VMs are portable and can move between physical systems running the same hypervisor.
Containers are more portable. They are smaller in size, boot up in less time. Docker containers can be run on any container service.
VMs are separated as each VM runs its own OS.
Containers are less separated since they all run on same OS.
If one OS crashes, other VMs are not affected.
If one OS crashes, all the containers crash.
Even though there is a major shift towards the use containers especially due to adoption of automation and DevOps, VMs are still widely used today and will continue to be used.
How do Containers Work?
Containers are built using containerization engines such as Docker, Kubernetes, etc. The containerization engine is responsible for creating, deploying, and managing containers.
When a developer creates a container, it contains all the necessary components required to run the application. This invovles the application code, runtime, system tools, along with the libraries. The container runs independently of other containers on the same server or cloud provider.
Containers use a host operating system, which means that they share the same kernel as the host. This results in faster startup times and lower resource consumption. When a container is started, it runs in its own isolated environment, with access to the resources it needs to run the application. This ensures that the container does not interfere with other containers or the host system.
Benefits of Containers in Cloud Computing
Containers are highly portable and can run on any server, cloud provider, or local environment without any issues.
Containers are lightweight and consume fewer resources compared to traditional virtual machines. This makes them perfect for deploying applications at scale.
Containers are isolated from each other, which helps in avoiding conflicts between different applications.
Containers ensure that the application runs in the same environment regardless of where it is deployed. This eliminates the risk of any unexpected behavior due to environmental differences.
5. Fast deployment:
Containers enable fast deployment of applications, as they can be easily created, started, and stopped within seconds.
In conclusion, containers are a game-changer in the world of cloud computing. They offer numerous benefits over traditional virtual machines, including portability, efficiency, isolation, consistency, and fast deployment.
By understanding how containers in cloud computing work, developers can use this technology to build and deploy applications more efficiently. In fact, it is also helpful for Network Engineers or DevOps Engineers for automation and programmability.