Kamaji vs Karmada

Kamaji runs Kubernetes control planes as pods inside a management cluster, giving platform teams a way to operate multiple tenant clusters. Each tenant control plane is independent and separated from others. It uses upstream Kubernetes components and kubeadm, with CNCF-conformant tenant clusters. Worker nodes may run on bare metal, virtual machines, or cloud instances across cloud, data-center, edge, and bare-metal environments. Kamaji integrates with Cluster API for infrastructure provisioning and lifecycle management, and supports cluster provisioning, multi-cluster management, policy enforcement, and upgrade management. Datastores include etcd and MySQL- or PostgreSQL-compatible databases through kine; NATS support is experimental. Konnectivity, enabled by default, creates secure tunnels to worker nodes. Prometheus-format metrics cover management and tenant planes. Metrics endpoints use unauthenticated plaintext by default, with documented HTTPS and bearer-token options. Kamaji is free under Apache 2.0; Clastix also sells enterprise support.

Karmada manages cloud-native applications across multiple Kubernetes clusters and clouds without requiring changes to the applications. It supports public and private cloud, on-premises, edge, and self-built environments that meet Kubernetes specifications. Cluster connections can use Push mode through a Kubernetes API server or Pull mode through an in-cluster agent. Scheduling policies cover cluster affinity, taints and tolerations, topology spread, and replicated or divided placement. OverridePolicy allows per-cluster changes to images, arguments, commands, and plain-text configuration. Karmada can move replicas after a cluster failure, including migration that avoids service replicas dropping to zero. Through karmada-apiserver, teams can create, update, delete, and query resources across member clusters. Its components export Prometheus metrics; integrations described include Submariner networking and ErieCanal service governance. Installation options include CLI tools, Helm, an operator, binaries, or source. The CLI initialization requires escalated privileges to store shared configuration under /etc/karmada by default. Karmada is open source and free, with customer-managed control plane; it manages clusters but does not provision them.