PlantUML — Kubernetes

@startuml
!theme plain
skinparam backgroundColor transparent
skinparam linetype ortho
title Kubernetes cluster topology

rectangle "Control plane" as ctl #fef3c7 {
  component "api-server" as api
  database  "etcd" as etcd
  component "scheduler" as sched
  component "controller-mgr" as ctrl
}
rectangle "Node 1" as node1 #dbeafe {
  component "api pod" as pod1a
  component "worker pod" as pod1b
  component "kubelet" as kub1
}
rectangle "Node 2" as node2 #dbeafe {
  component "api pod" as pod2a
  component "redis pod" as pod2b
  component "kubelet" as kub2
}

api --> etcd
api --> sched
api --> ctrl
api ..> pod1a : assigns
api ..> pod1b : assigns
api ..> pod2a : assigns
api ..> pod2b : assigns
kub1 --> api
kub2 --> api
@enduml