Architecture

Architecture

Separation of frontend and backend

KubeSphere separates frontend from backend, and it itself is a cloud native application and provides open standard REST APIs for external systems to use. Please see API documentation for details. The following figure is the system architecture. KubeSphere can run anywhere from on-premise datacenter to any cloud to edge. In addition, it can be deployed on any Kubernetes distribution.

Components List

Back-end component	Function description
ks-account	Account service provides APIs for account and role management
ks-apiserver	The KubeSphere API server validates and configures data for the API objects which include Kubernetes objects. The API Server services REST operations and provides the frontend to the cluster’s shared state through which all other components interact.
ks-apigateway	The API gateway is responsible for handling external requests for KubeSphere services.
ks-console	KubeSphere console offers KubeSphere console service
ks-controller-manager	KubeSphere controller takes care of business logic, for example, when create a workspace, the controller will automatically create corresponding permissions and configurations for it.
metrics-server	Kubernetes monitoring component collects metrics from Kubelet on each node.
Prometheus	provides monitoring metrics and services of clusters, nodes, workloads, API objects.
Elasticsearch	provides log indexing, querying and data management. Besides the built-in service, KubeSphere supports the integration of external Elasticsearch service.
Fluent Bit	collects logs and forwarding them to ElasticSearch or Kafka.
Jenkins	provides CI/CD pipeline service.
SonarQube	is an optional component that provides code static checking and quality analysis.
Source-to-Image	automatically compiles and packages source code into Docker image.
Istio	provides microservice governance and traffic control, such as grayscale release, canary release, circuit break, traffic mirroring and so on.
Jaeger	collects sidecar data and provides distributed tracing service.
OpenPitrix	provides application lifecycle management such as template management, deployment, app store management, etc.
Alert	provides configurable alert service for cluster, workload, Pod, and container etc.
Notification	is an integrated notification service; it currently supports mail delivery method.
Redis	caches the data of ks-console and ks-account.
MySQL	is the shared database for cluster back-end components including monitoring, alarm, DevOps, OpenPitrix etc.
PostgreSQL	SonarQube and Harbor’s back-end database
OpenLDAP	is responsible for centralized storage and management of user account and integrates with external LDAP server.
Storage	built-in CSI plug-in collecting cloud platform storage services. It supports open source NFS/Ceph/Gluster client.
Network	supports Calico/Flannel and other open source network plug-ins to integrate with cloud platform SDN.

Service Components

Each component has many services, see Service Components for more details.