1.8 KiB
1.8 KiB
| title | updated | created | latitude | longitude | altitude |
|---|---|---|---|---|---|
| K8s Architecture | 2022-01-29 16:47:31Z | 2022-01-29 16:19:16Z | 52.38660000 | 5.27820000 | 0.0000 |
Worker Machine in K8s cluster
- Nodes do the actual work
- each node has multiple Pots on it
- 3 process must be installed on every Node
- Container Runtime (eq Docker)
- Kubelet
- interacts with container and node
- starts the Pod and the container inside
- assigns resources from Node to the container
- Communication between Nodes through Services
- Kube Proxy
- forwards the requests
Master Node (usally multple master nodes)
- 4 processes that must un on every master Node that control the master state and the workers
- API Server(client interacts with this api)
- acts as a load balances for the master nodes
- require much less resources then worker nodes
- more worker nodes, then more master nodes => makes the application more robust
- cluster gateway
- gets initial request like update or query
- acts as a gatekeeper for authentication
- validates a request and when OK it forwards the request to other processes and eventually to the Pod.
- One entry point to the cluster
- Scheduler
- API Server sends request to Scheduler and will start a Pod
- Has intelligence with Pod has to complete the work (how much cpu, ram etc)
- Kubelet gets the request and executes the request
- Controller manager
- detects cluster state changes like crashes
- tries to recover the state by making a request to the Scheduler
- etcd (key value store off the cluster state) (cluster brain)
- other 3 components get the information from etcd
- does not contain any application data!
- distributed across all the master nodes
- API Server(client interacts with this api)