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Declarative configuration for Cluster Overrides

Cluster overrides

By default, K8s objects require certain values be set inside their specs that match the cluster's configuration. If this were to done within the add-on (or workload) manifest, it would require that many duplicate add-ons (or workloads) would need to be created for a fleet of clusters. To mitigate this, the platform supports cluster overrides. These allow the customer to use a single add-on (or workload) org wide and dynamically inject values into a manifest as it is being deployed to the cluster.

Examples include:

  • Use of a different license key for a security tool based on the business unit

  • Configuration of different resource requests for a monitoring tool based on environment type (test or prod)

  • Dynamic configuration of cluster name during deployment of a load balancer (e.g. AWS Load Balancer)

Declarative usage pattern

Every Kubernetes user is familiar with the kubectl apply command. This is used to create or modify Kubernetes resources as defined in a manifest file. This pattern is referred to as Declarative usage where the state of the resource is "declared" in the manifest file and the command is used to implement the declared state. Unlike an imperative approach where the user needs to specify both what and how to perform a task, with the declarative approach, the user just needs to specify what to do and not worry about how to do it.

The apply approach is preferred and recommended because it is well suited for version control. The kubectl apply command works extremely well for resources inside the Kubernetes cluster.

Rafay supports a similar declarative usage pattern for the platform resources. A recent release adds support for the apply pattern for Cluster Overrides.

This makes it extremely simple for customers to maintain version controlled declarative specifications for their cluster overrides and embed Rafay's RCTL CLI into their automation pipelines. The significant advantage is that the business logic they need to implement in their pipelines is BRUTALLY SIMPLE. In a nutshell, the pipeline needs to worry about just 2 commands (apply and delete) in the RCTL CLI.

For more information on the declarative spec to be used for Add-ons/Workload cluster overrides, please refer here.

Try It Out

Sign up here for a free trial and try it out yourself. Get Started using Rafay includes a number of hands-on exercises that will help you get familiar with capabilities of Rafay's Kubernetes Operations and Environment Manager capabilities .

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