On the internet, there's a wealth of information about Kubernetes, Docker, and containerisation. However, we've chosen to tackle this topic from our Proxy point of view: simply and concisely. Here's our 'submission', affectionately dubbed YACA (Yet Another Containerisation Article).
- Go directly to:
- Benefits of Containerisation
Introductie
Containerisation is a technology that has revolutionised the way we develop, deploy, and manage software. It has transformed the landscape of software development by enabling applications to be isolated from their environment and packaged, shipped, and executed consistently, regardless of where they are hosted. In this whitepaper, we will explore containerisation in detail, from its basic principles to its benefits and applications.
What is Containerisation?
Before delving deeper into containerisation, it's important to first understand what containers are and how they work. A container is a standardised, lightweight unit of software that contains all the necessary code, runtime, system tools, and libraries required to run a specific software application. In simple terms, containers can be thought of as packages that encompass everything an application needs to run.
Containerisation is the process of creating, deploying, and running containers. It relies on container management technologies such as Docker, Kubernetes, and others. These technologies provide a standardised way to create and manage containers, enabling developers and operational teams to work more efficiently.
How does Containerisation work?
Containerisation utilises several key concepts and technologies to create and manage containers:
Engines
A container engine, such as Docker, is responsible for building, running, and managing containers. It provides a straightforward way to create containers through container images, which serve as templates for containers.
Images
A container image is an executable package that contains all the necessary components to run an application. It includes the application code, runtime, system tools, libraries, and other dependencies required to make the application work. Container images are used as blueprints for containers.
Orchestration
Container orchestration is the process of automating the deployment, management, and scalability of containers. This is often accomplished using orchestration tools like Kubernetes, which can distribute containers across multiple hosts, automatically scale, and recover from failures.
Containerisatie versus servervirtualisatie
When people talk about server virtualisation, they usually refer to a virtual machine (VM). A VM creates a hypervisor layer (a type of software responsible for server virtualisation) between the operating system, applications, services, memory, and storage.
This layer acts as its own VM, creating a standalone environment to run a single application or service. Each virtualised application consumes its own instance of an operating system. To develop in a virtual environment, you always need the following:
1. Different available versions of the operating system
2. Multiple licenses (purchasing)
On the other hand, containers enable multiple applications to run on a single VM. This reduces the number of software licenses a company needs to invest in to develop in a container environment. They achieve this by sharing the operating system (OS) kernels, rather than requiring their own operating system.
Therefore, developing in a container is a more efficient approach, both financially and in terms of smartly sharing the computing power of a VM. This makes you less vulnerable to changes and allows for seamless updates or scaling up when a peak is imminent. But above all, the decoupling of dependencies makes it highly flexible to develop and manage applications using container technology.
Benefits of Containerisation
Containerisation offers a wide range of benefits for both developers and operational teams:
Isolation:
Containers provide isolated environments for the applications they run. Each container has its own file system, processes, user space, and network stack, keeping applications separate from each other. This minimises the chance of interference between applications and helps limit the impact of security vulnerabilities.
Shared Kernel:
Containers utilise the host operating system's kernel, meaning they share kernel resources. This reduces the surface area for potential attacks since there are fewer components to secure compared to using separate kernels for each virtual machine.
Faster patching and updates:
Due to containers being smaller and lighter than virtual machines, patches and updates can be applied more quickly. This reduces the time vulnerabilities remain open and decreases the likelihood of exploitation by malicious actors.
Limited privileges:
Containers often run with limited privileges, meaning they only have access to the resources and capabilities they need to function. This minimises the risk of abuse if a container becomes compromised.
Managed environment:
Containers can be managed and orchestrated using dedicated tools such as Kubernetes, Docker Swarm, and others. These tools provide features such as network isolation, authorisation, authentication, and monitoring, contributing to overall improvement in the security of container environments.
Different Types of Container Applications
Containerisation is used in a wide range of applications and industries:
Web Applications:
Containers are widely used for deploying web applications, where each container can contain a specific component of the application, such as the front-end, back-end, and database.
Continuous Integration/Continuous Deployment (CI/CD):
Containers are used in CI/CD pipelines to automate and speed up the deployment of applications.
Data Analysis:
Containers are used for running data analysis workloads, where containers can be scaled depending on the amount of data that needs to be processed.
Internet of Things (IoT):
Containers are used in IoT applications for deploying edge computing workloads, where containers are deployed on devices at the edge of the network.
Machine Learning and Artificial Intelligence:
Containers are used for deploying machine learning models and AI applications, where containers can be scaled to meet the workload requirements.
In Summery
Containerisation is a powerful technology that has revolutionised the way we develop, deploy, and manage software. By leveraging containers, developers and operational teams can work more efficiently, deploying applications faster and more reliably. With benefits such as portability, scalability, and isolation, containerisation has become an essential component of modern software development.
Containerisation in a Managed Platform
Platform as a Service (PaaS) provides developers with an integrated environment for designing, developing, testing, and deploying applications without having to worry about the underlying infrastructure. Within PaaS environments, containers play a crucial role in packaging and delivering applications, providing developers with a streamlined workflow and improving operational efficiency.
The platform plays an essential role in managing and publishing software. In a PaaS approach, this aspect is completely decoupled from the expertise in software development. This means that the various aspects of containerisation can be managed and configured separately.
