Everything You Should Know About Container Orchestration

Containers are cloud-based software packages bundling code, libraries, and dependencies that facilitate building modern applications. Container orchestration has become essential for building complex apps that run seamlessly in any environment. 

Using container orchestration tools, top software development companies deploy, scale and manage containerized application infrastructure. Container orchestration enables deploying self-contained units at scale with lower maintenance costs. It also addresses the challenges of managing multiple containers by supporting container creation, orchestration and automating container lifecycle management through a single interface. 

As container orchestration is a relatively new concept, challenges may arise. However, by following best practices and selecting the right tool that fits your requirements, you can ensure enhanced performance and achieve desired outcomes. Let us explore the benefits, challenges, and best practices of container orchestration along with its practical working.

1. What is Container Orchestration?

Container orchestration refers to the method of managing multiple containers, ensuring that each one runs efficiently. Software developers use container orchestration tools to achieve this. These tools automate the management and monitoring of containers across single or multiple machines, based on your needs. 

All operational efforts needed to run containerized services and workloads are easily automated through the container orchestration process. This includes lifecycle management for containers, covering services such as load balancing, scaling, provisioning, networking and deployment. Even when managing an app with a large number of containers running across different environments, container orchestration ensures reliability and organizational efficiency.

2. Why Do You Need Container Orchestration?

Containers are lightweight and short-lived. Therefore, running them in a production environment requires significant manual effort, especially when paired with microservices. In a microservices architecture, every microservice runs in its own container, and there can be hundreds or even thousands of such containers in a large-scale application. 

Naturally, the complexity increases if such an app is managed manually. This is where container orchestration reduces operational complexity by breaking it down into small, manageable DevOps activities. It provides a declarative way to automate most tasks. Container orchestration is ideal for DevOps teams, enabling them to adapt and deliver quickly compared to traditional teams. 

Before container orchestration, these challenges were addressed with complex scripting, which handled container deployment, deletion, scheduling and more. However, scripting came with its own challenges, such as difficult setup and version control issues. Container orchestration not only resolves these issues but also automates the entire process, eliminating manual intervention.

3. Use Cases of Container Orchestration

Container orchestration automates and manages various operations throughout a container’s lifecycle, including: 

• Organizing and scaling containers
• Running multiple self-contained units simultaneously
• Deploying different app versions
• Running duplicate instances to ensure uninterrupted performance
• Maximizing server instances utilization to reduce costs
• Provisioning and deployment
• Configuration and scheduling
• Resource allocation
• Ensuring container availability
• Scaling or removing containers to balance workloads across the infrastructure
• Load balancing and traffic routing
• Monitoring container health
• Configuring applications based on the container environment
• Securing interactions between containers 
• Migrating containers between hosts

4. Benefits of Container Orchestration

There are many benefits of using container orchestration, some of which are discussed below: 

4.1 High Resilience and Availability

When a container fails, container orchestration tools automatically restart or scale the cluster or container, increasing resilience. This improves availability and app uptime. In addition to automated failure recovery, load balancing and built-in redundancy also contribute to higher uptime. 

4.2 Enhanced Resource Usage and Performance

Smart distribution of workloads across the available infrastructure improves hardware efficiency and reduces resource wastage. Moreover, automated host selection and resource allocation features ensure maximum efficiency of the resources in use. For instance, a container orchestration tool adjusts storage and CPU memory to meet the specific needs of a container, preventing overprovisioning and enhancing performance. 

4.3 Speed and Agility

Using a container orchestration tool accelerates the development and deployment by offering critical support for cloud-native and DevOps processes, such as CI/CD, to add new features or functionalities, resulting in faster time to market. 

4.4 Improved Security

Containers isolate the app from the host system and from each other, significantly minimizing attack surfaces. Container orchestration tools perform regular scans to identify vulnerabilities and ensure the security of image registries. More importantly, their automated approach eliminates the risks of human errors, thereby enhancing application security. 

4.5 Simplified Process and Management

Containerized apps introduce significant complexity that can quickly become unmanageable. Implementing container orchestration not only helps control this complexity but also offers centralized management of complex environments. Container orchestration provides a single interface through which IT teams can handle everything- from deployments and updates to security policies. 

Moreover, container orchestration tools automatically load balance and scale microservices, boosting the resiliency of the entire system while avoiding unnecessary operational complexities. 

5. How Does Container Orchestration Work?

Containers are self-contained, Linux-based apps or microservices that include the necessary functions and libraries to run on any machine. Container orchestration refers to the process of managing containers across multiple server instances, also known as nodes. A cluster is a group of nodes running interconnected containers. 

Each node runs a containerization platform, such as Docker, along with an orchestration tool. A designated master node uses the control plane to control the running orchestration solution. The solution’s administrator can monitor and manage the CO tool by using a command-line controller or a GUI. 

5.1 Provisioning

A declarative configuration file is normally written in either JSON or YAML format. The container orchestration (CO) tool reads this file to understand the desired state of the system. Leveraging the information from the file, the tool can perform the following tasks: 

• Fetch container images from the container registry.
• Fulfill the individual requirements of each container.
• Determine the networking required between containers. 

5.2 Deployment

The CO tool manages the scheduling and deployment of a multi-container application across the cluster. Rather than relying solely on the configuration file, the tool selects the optimal match between containers and nodes. It considers the container requirements and the node resource constraints, like memory and CPU, to determine the appropriate node to run each container. 

5.3 Lifecycle Management

After deploying the containers, orchestration tools handle every aspect of the containerized app’s lifecycle by referring to the container definition file, often a Dockerfile. Below are some key lifecycle management operations: 

• Managing container scalability. 
• Load balancing containers. 
• Ensuring proper resource allocation for each container. 
• Relocating containers to another host in case of resource shortages or outages to maintain performance and availability. 
• Monitoring application performance and health by gathering and storing log data along with other required telemetry. 

Container orchestration platforms enable development teams to optimize and secure large and complex multi-container environments and workloads by simplifying container lifecycle management. Regardless of how many containers your organization requires, the right CO tool can efficiently handle them all. Ensuring availability and fault tolerance is a common demand among large organizations, which a CO tool can easily fulfill by running multiple master nodes.

6. What are the Challenges of Container Orchestration?

Along with its benefits, container orchestration also presents some challenges. It is important to understand these challenges to stay prepared for maximum outcomes.

6.1 Insufficient Training

Container orchestration won’t be beneficial if your team doesn’t know how to use them effectively. A skilled tool administrator is required to efficiently manage the orchestration, define the desired state, and interpret monitoring outputs. They must also have a working knowledge of machine architecture, containerization, CI/CD, and DevOps processes. This expertise helps them successfully navigate the complexities of managing multiple container environments. Therefore, training your staff is essential to ensure these capabilities are in place. 

6.2 Versioning Configurations

Similar to versioned software applications, container orchestration tools maintain multiple configurations with version histories. This enables repeatable provisioning, as well as quick management and deployment. However, configurations must be precise to accommodate varying environments and other requirements. Containerized apps need configurations related to access controls, networking policies, and resource limits. Tracking and scaling these configurations across all versions can be challenging. 

6.3 Scalability Challenges

Containerized apps can be resource-intensive. Therefore, when scaling your app, you need an orchestration platform capable of meeting its demands at any given time. If you cannot quickly address the app’s increasing resource requirements, then another solution is to purchase premium features like autoscaling to reduce the risks of crashes. Although some free options exist to help maintain your app’s functionality without affecting reliability and performance, they offer limited support under heavy load.

7. Top Container Orchestration Tools

These tools provide all the necessary components for enabling container orchestration in organizations of any scale. 

7.1 Docker Swarm

Docker Swarm is a native feature of the Docker Engine. This container orchestration tool allows you to cluster a pool of Docker hosts or nodes into a single virtual Docker engine for unified management. It operates with two main components: 

1. Manager Nodes: They oversee cluster-level duties and maintain the declarative desired state. 
2. Worker Nodes: They perform the tasks assigned by the manager nodes. 

Native clustering, decentralized design, automatic load balancing, high security, and rolling updates are the key features of Docker Swarm that simplify the setup and management of high-availability applications.

7.2 Amazon Elastic Kubernetes Service (EKS)

Build, launch, and scale Kubernetes apps on the AWS cloud or on-premises with the help of EKS. This CO tool is compatible with existing Kubernetes plugins and tools, making it easy to automate routine tasks such as patching, updates, and node provisioning. 

Through automatic deployment of the Kubernetes control plane with three master nodes across multiple Availability Zones, EKS ensures high reliability and resilience. This architecture reduces the mean time to recovery and prevents a single point of failure. 

Kubernetes Role-Based Access Control (RBAC) is integrated with AWS Identity and Access Management (IAM) to meet security requirements. Furthermore, EKS offers flexible control planes and add-ons to simplify cluster management, scaling, and updating apps within a managed Kubernetes ecosystem. 

7.3 Kubernetes (K8s)

Initially, K8s was created by Google but is now maintained by the Cloud Native Computing Foundation (CNCF). Its primary use cases include automated deployment, scaling, and management of containerized applications and services. 

Kubernetes supports declarative configuration, enabling effective management. This helps automate numerous manual operations such as deployment, load balancing, and the management of containerized applications across diverse infrastructure. The core framework includes a cluster, which can consist of physical or virtual nodes used to host application workloads inside Pods. 

Key features of Kubernetes include automated rollouts and rollbacks, built-in service discovery, self-healing mechanisms, and horizontal scaling. Development teams use this container orchestration tool to scale their applications across multiple clusters, containers, and cloud environments. 

The open-source nature of Kubernetes has attracted significant contributions from its community. Notably, it offers an extensive library rich with functionalities and unparalleled capabilities for microservices management. This is why Kubernetes serves as the foundation for most managed orchestration solutions. 

7.4 Nomad

Created by HashiCorp, Nomad is a modern and versatile workload orchestration tool renowned for its simplicity and single-binary operation. Unlike specialized orchestrators, Nomad is highly flexible and supports both containerized and non-containerized applications across diverse computing environments. It uses a declarative infrastructure-as-code approach to describe configurations for deployment and management in both cloud and on-premise data centers. 

Nomad offers a simple, unified workflow, supports multiple data centers and regions, and can scale to thousands of nodes. It integrates seamlessly with other HashiCorp platforms like Terraform, Consul, and Vault, improving reliability and scalability.

7.5 Red Hat OpenShift

Red Hat OpenShift is a comprehensive container application platform that extends and enhances Kubernetes for enterprise use across hybrid cloud environments. Developed by Red Hat, it is a managed orchestration solution focused on running containers on-premises, in a private cloud, or in hybrid environments.

The platform is tightly integrated with Red Hat Enterprise Linux and automates the lifecycle management of containerized applications. It offers features like an integrated development environment, automated installation and upgrades, a container image registry, and advanced networking capabilities.

OpenShift simplifies production workflows by enabling continuous integration through built-in Jenkins pipelines. It also provides a rich set of built-in components like monitoring and service mesh that are optional extras in standard Kubernetes. 

The platform supports both Platform-as-a-Service (PaaS) and Container-as-a-Service (CaaS) models and includes tools like the Embedded Operator Hub and the Red Hat Marketplace for easy access to services and applications.

8. Conclusion

Container orchestration is essential for businesses aiming to reduce costs and increase efficiency. But it can sometimes be overwhelming. As the number of containers grows, so does the complexity, and with so many components operating simultaneously, it becomes difficult to manage everything effectively. On top of that, there are significant technical challenges to address. Nevertheless, by carefully assessing your requirements, preparing a detailed strategy, and using the right tools, the outcomes can be highly beneficial.

FAQs

Is Kubernetes a container orchestrator?

Yes, Kubernetes is a container orchestrator that automates the deployment, scaling, and management of applications by coordinating containers across a cluster of machines.

When to use container orchestration?

You can use container orchestration in the following scenarios: 

• Scaling and managing containers across multiple instances. 
• Running different containerized applications.
• Running different versions of applications, such as test and production, across CI/CD simultaneously. 
• Running multiple container instances to maintain app service continuity in case of server failure. 
• Running multiple instances of an application across multiple geographical regions.
• Maximizing the utilization of multiple server instances to optimize budgeting.
• Running large containerized applications composed of thousands of microservices.

What is Docker Swarm vs Kubernetes?

It is a comparison between two popular container orchestration tools against important parameters to determine which one is the right fit for your projects