Anthos Overview

Anthos is Google Cloud's application platform for modernising existing applications, building new ones, and running them consistently across on-premises data centres, Google Cloud, and other cloud providers. It provides a unified management layer built on Kubernetes, enabling consistent operations regardless of where your workloads run.

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What Is Anthos?

Anthos is a suite of products and features that extends Google Cloud's managed Kubernetes and service mesh capabilities beyond Google Cloud. It enables organisations to run Kubernetes clusters on-premises, on Google Cloud (GKE), on AWS, and on Azure — all managed from a single control plane.

Core Components

Component	Description
GKE Enterprise	Enhanced GKE with fleet management, multi-cluster features, and governance
GKE on-prem (Anthos clusters on bare metal/VMware)	Run Kubernetes on your own hardware, managed by Google
Anthos clusters on AWS/Azure	Run Google-managed Kubernetes on other cloud providers
Anthos Service Mesh	Managed Istio service mesh for observability, security, and traffic management
Anthos Config Management	Policy and configuration management across all clusters using GitOps
Binary Authorization	Enforce deploy-time security policies — only approved images can be deployed
Migrate to Containers	Migrate VMs to containers without rewriting applications

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Fleet Management

Anthos introduces the concept of a fleet — a logical grouping of Kubernetes clusters that can be managed as a single unit. Fleets enable:

Feature	Description
Multi-cluster management	View and manage all clusters from one dashboard
Consistent policy	Apply policies across all clusters in the fleet
Namespace sameness	A namespace with the same name across clusters is treated as the same namespace
Multi-cluster services	Discover and route traffic across clusters in the fleet
Fleet-wide RBAC	Apply RBAC roles across all clusters

# Register a cluster to a fleet
gcloud container fleet memberships register my-cluster \
  --gke-cluster europe-west2/my-cluster \
  --enable-workload-identity

# List fleet members
gcloud container fleet memberships list

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Anthos Config Management

Anthos Config Management (ACM) provides GitOps-based policy and configuration management for fleets of clusters. It consists of:

Config Sync

Config Sync continuously syncs Kubernetes configurations from a Git repository to your clusters. Any changes committed to Git are automatically applied to the target clusters.

Policy Controller

Policy Controller (based on OPA Gatekeeper) enforces security and compliance policies across all clusters. You define constraints using policy templates, and Policy Controller rejects any resource that violates the constraints.