CAST AI Components Hosted On Customers' Clusters

The CAST AI connection process installs several components into a customer's cluster in phases, providing different levels of functionality:

• Phase 1: Provides visibility into connected clusters without the ability to tune them. This phase operates in a read-only mode.
• Phase 2: Enables full functionality of the CAST AI platform, primarily for cluster optimization. In this phase, CAST AI can instruct clusters and Cloud Providers to reorganize resources for optimal performance.

Phase 1 Component - CAST AI Kubernetes Agent

The CAST AI Agent is the first component installed when connecting a new cluster. It runs as a Pod in a dedicated CAST AI namespace:

» kubectl get pods -n castai-agent
NAME                                         READY   STATUS    RESTARTS   AGE
castai-agent-7f9d7ff65b-8qm7p                1/1     Running   0          78m
castai-agent-cpvpa-56f749fb-n2wzp            1/1     Running   0          22d

• The CAST AI Kubernetes Agent is responsible for sending cluster state data (snapshots) to the main system.
• The Cluster Proportional Vertical Autoscaler adjusts allocated resources for castai-agent Pods based on a predefined formula.

Phase 2 Autoscaling Components

When a connected cluster is promoted to Phase 2, CAST AI installs additional components to enable cost savings through cluster management:

❯ kubectl get pods -n castai-agent
NAME                                             READY   STATUS    RESTARTS   AGE
castai-agent-7f9d7ff65b-8qm7p                    1/1     Running   0          80m
castai-agent-7f9d7ff65b-kf2zp                    1/1     Running   0          5h7m
castai-agent-cpvpa-56f749fb-n2wzp                1/1     Running   0          22d
castai-cluster-controller-757997ff6c-r6x25       1/1     Running   0          27d
castai-cluster-controller-757997ff6c-xw54g       1/1     Running   0          27d
castai-evictor-5684748495-kl2q4                  1/1     Running   0          22d
castai-kvisor-787c5dd946-gmzs5                   1/1     Running   0          6d18h
castai-spot-handler-44shj                        1/1     Running   0          43m

• The Cluster Controller executes actions received from the central platform, such as accepting newly created nodes into the cluster.
• The Evictor removes pods from underutilized nodes to reduce the overall number of cluster nodes.
• The Spot Handler monitors scheduled events (provided by Instance Metadata Service) and relays them to the central platform. It is installed as a DaemonSet rather than a regular Deployment.

Phase 2 Security Component - Kvisor

• Kvisor performs image vulnerability scanning, Kubernetes YAML manifest linting, and provides CIS security recommendations.

User Roles

CAST AI offers the following predefined roles:

• Owner: Full access to clusters, billing, and organization management.
• Member: Full access to clusters, view-only access to billing.
• Analyst: Full access to cost monitoring, view-only access to clusters, and billing.
• Viewer: View-only access to clusters and billing.

This guide outlines the key components and roles within the CAST AI platform, providing an overview of its functionality and integration with customer clusters.