Introduction to Argo CD: Your best GitOps friend for deploying applications in Kubernetes
GitOps is a framework that automates the process of provisioning infrastructure, especially modern cloud infrastructure. Operations Teams that adopt GitOps use configuration files stored as code (infrastructure as code), similar to how Teams use application source code. These configuration files generate the same infrastructure environment every time they’re deployed, just as application source code generates the same application binaries every time it’s built.
Although much of the software development lifecycle has been automated, infrastructure has remained a largely manual process that requires specialised Teams. With the demands placed on today’s infrastructure, it has become increasingly crucial to implement infrastructure automation. Modern infrastructure needs to be elastic to effectively manage cloud resources needed for continuous deployments.
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So, the challenges that GitOps needs to respond are:
- Improving high level of collaboration within Team
- Reducing the effort for infrastructure changes (time, manual changes)
- Improving the Security
- Guaranteeing Reliable Infrastructure
- Keeping Application Consistency
What is Argo CD?
Argo CD is a declarative, GitOps Continuous Delivery (CD) tool which extends the Kubernetes orchestration functionalities.
Below is an example of the Argo CD architecture:
The base concept around Argo CD, since it is a GitOps based tool, is that the Git repository is the single source of truth.
Argo CD compares the Desired State, which represents the application files inside the repository, and the Live State, which represents the real application deployed inside the Kubernetes cluster.
Git as Single Source of Truth
Since the GitOps framework regulates the Infrastructure deployment, the Git Repository is crucial in our deployment and considered the only interface for Argo CD. ArgoCD orchestrates the deployments in the Kubernetes cluster, maintaining the tracing of each deployment, the infrastructure reliability and the integrity of the application.
Better Team Collaboration
Manual changes to the infrastructure cluster are not allowed if Argo CD is in charge. This forces Teams to improve collaboration and communication before introducing a change, which ultimately leads to better code quality and improved infrastructure reliability.
K8s Access Control with Argo CD
Access to the Kubernetes cluster can only be controlled through Argo CD. Direct infrastructure changes are denied, and Argo CD is delegated to apply any necessary changes.
This approach ensures that any changes made to the infrastructure are done in a controlled and secure way. By delegating the responsibility of applying changes to Argo CD, teams can ensure that changes are made in a consistent and reliable manner, which ultimately leads to better code quality and infrastructure reliability.
Diffing and drift detection
If someone manually changes the application on a Kubernetes cluster, Argo CD will detect it because the Desired State (from Git Source) and the Live State (Kubernetes cluster) will be different.
Argo CD has a feature called selfHeal that prevents this kind of situation. Whenever it detects a drift in the configuration, it replaces the latest state bound to the commit ID in the Git repository.
In a nutshell
- Declarative tool for Continuous Delivery of the Kubernetes applications
- Control plane that extends GitOps for Infrastructure deployments in Kubernetes
- Live State vs Desired Target State
- Scalability, Multi-tenancy, Security, Extensibility
- Application Sync Automation
- Drift detection and diffing
- Real-Time Application State
- Auditing and Tracing
- Helm Chart Orchestrator
- Kustomize compatible
Argo CD is your best friend for GitOps because it provides a declarative, GitOps approach to continuously deliver Kubernetes applications. With Argo CD, you can automate application synchronisation, detect drift, and access real-time application state. Additionally, Argo CD provides auditing and Helm chart orchestration, making it an all-in-one solution for your Kubernetes deployment needs.
At Hivemind Technologies we have huge experience in migrating monolith applications into Kubernetes cloud services, such as AWS and Azure, and transforming the processes for deploying your services with scalability, flexibility, and reliability.
Additionally, we can integrate Argo CD with Kubernetes and manage the Continuous Integration and Continuous Delivery (CI/CD) of application deployment, the operational state through the observability and tracing platform, and the cluster’s compute resource footprint to reduce costs and improve performance.