A platform team can face significant challenges when it comes to operating a dynamic Kubernetes environment with multiple clusters spanning development, testing, and production.
- Frequent code deployments: In modern application environments, code changes frequently—often multiple times per day. Frequent infrastructure configuration adjustments may be necessary to keep up with code changes.
- Continued scaling: clusters need to scale to keep pace with new applications, new features, and increased activity.
Trying to handle infrastructure configuration needs manually can be a recipe for disaster, requiring too much admin time and introducing configuration errors that can take time to troubleshoot. Even more concerning, misconfigurations can result in security vulnerabilities that invite cyberattacks.
Automation is the best way to increase efficiency, decrease manual errors, ensure security and reliability, and help standardize your operations by making infrastructure configuration standardized and repeatable.
In the mid-2000s, the concept of Infrastructure as Code (IaC) emerged in response to challenges like these. By specifying configuration information in written form, infrastructure configuration can be automated and manual errors are avoided. This article explains IaC and explains why GitOps is a natural extension of IaC.
What is Infrastructure as Code?
With IaC, configuration files automate the provisioning and management of infrastructure. It’s an approach that is especially useful for configuring infrastructure for cloud deployments as well as virtual machines and containers running in the cloud or on-prem.
As with other software, once the “code” that specifies an infrastructure configuration is created, it can be applied again and again, producing the same result each time. The creation of production, development, and test environments becomes versionable, testable, and repeatable.
This approach has proved so useful that a whole ecosystem of tools has grown up to enable Infrastructure as Code. The most popular tools include: Chef, Puppet, Ansible, and the open-source Terraform. Many DevOps teams used—and may still use—these tools to streamline DevOps.
Benefits of IaC include:
- Shorter time to production: Provision infrastructure more quickly while reducing human error and achieving predictable results.
- Reusability: An IaC configuration file acts as a template that can be used as a starting point for additional, related configuration needs.
- Consistency: Deploy the same infrastructure over and over without accidentally introducing subtle differences that may result in major challenges down the road.
- Configuration tracking and auditing: Combining IaC with a code repository for source tracking, provides a change history, versioning, and an audit trail that shows who made changes and when.
- Increased institutional knowledge: Versioning can capture the reasons why changes were made. This record is available to employees new and old.
- Disaster recovery: IaC helps ensure you can rebuild a crashed or failed environment and get back to business more quickly.
What is GitOps?
IaC automates all the manual steps necessary to configure VMs, containers, network settings, storage, etc. resulting in configured infrastructure that is ready for code deployment. GitOps builds on the concept of IaC, incorporating the functionality of Git repositories, merge requests (MRs) and CI/CD to further unify software development and infrastructure operations.
Using the same approach for managing infrastructure configuration files as for software code enables teams to collaborate more effectively on infrastructure changes and vet configuration files with the same rigor as software code.
GitOps leverages Git as a single source of truth for both infrastructure and applications. Because GitOps is declarative, it provides for better standardization, enhanced security, and improved productivity.
Although GitOps is not exclusively applicable to Kubernetes, the core principles align well with the underlying design principles of Kubernetes, which is why GitOps and Kubernetes work well together. Popular open-source GitOps tools that work with Kubernetes include Flux and ArgoCD.
You can learn more about GitOps by reading the Rafay blog GitOps Principles and Workflows Every Team Should Know.
GitOps automates the configuration of infrastructure and the deployment of software code on that infrastructure. GitOps helps enforce traceability through a logical sequence of steps throughout the entire lifecycle. Here are the typical steps, focusing on infrastructure:
Step 1: Write a YAML file to describe the infrastructure configuration and store it in a Git repository. Using a repository enables version control and allows collaboration within and between teams.
Step 2: Complete a pull/merge request to ensure any necessary collaboration or approvals occur. Reviews and testing should occur before any production deployment. Doing so can significantly improve the results.
Step 3: Initiate a deployment through your CI/CD pipeline.
- Step 3a: A push deployment uses your CI/CD pipeline to trigger the job through a git action or a manual trigger.
- Step 3b: A pull deployment uses agents running on source infrastructure that continually monitor the desired state in the Git repository and compare it to the current state of the cluster. If there are changes in the desired state, the agent pulls the new configuration and applies it.
In a pull-based pipeline, a GitOps Kubernetes operator on each cluster watches for changes to the Git repository and pulls them into the cluster when they occur. In the push-based approach, repository updates trigger the build and deploy pipeline to push updates to each target cluster.
Pull-based GitOps pipelines have a number of advantages versus push-based ones. As a rule, pull-based GitOps is more secure and include active detection and remediation which can be highly beneficial.
IaC and GitOps at Rafay
Rafay’s GitOps Service simplifies automation for Kubernetes deployments by abstracting away the need for a deep understanding of Kubernetes. The Rafay Kubernetes Operations Platform is a SaaS platform that works with any Kubernetes distribution, across public clouds and remote/edge locations.
With Rafay’s GitOps Service, you can:
- Programmatically construct multi-stage GitOps pipelines for both applications and clusters
- Fully automate deployments and remove error prone, manual steps
- Guarantee that the desired state specified in your Git repos is instantly enforced on Kubernetes clusters
- Implement easy-to-use controls enabling developers and operations teams to collaborate
In addition to our GitOps Service, Rafay offers a number of additional capabilities to further streamline your Kubernetes and application deployments. Read the Rafay blog, Choosing the Best Kubernetes Cluster and Application Deployment Strategies to learn more.
Ready to find out why so many enterprises and platform teams have partnered with Rafay to streamline Kubernetes operations? Sign up for a free trial today and follow our quickstart guide to see what the Rafay GitOps Service can do.