Google Kubernetes Engine Flashcards
Google Kubernetes Engine (GKE)
Managed Kubernetes service
GKE Cluster :
Group of Compute Engine instances:
1. Master Node(s) - Manages the cluster
2. Worker Node(s) - Run your workloads (pods)
Master Node (Control plane) components :
- API Server - Handles all communication for a K8S cluster (from nodes and outside)
- Scheduler - Decides placement of pods
- Control Manager - Manages deployments & replicasets
- etcd - Distributed database storing the cluster state
Worker Node components :
Runs your pods
–> Kubelet - Manages communication with master
node(s)
Kubernetes - Pods
Smallest deployable unit in Kubernetes
A deployment is created for each microservice:
–> Deployment represents a microservice (with all its releases)
–> Deployment manages new releases ensuring zero downtime
Replica set
ensures that a specific number of pods are
running for a specific microservice version
ClusterIP:
Exposes Service on a cluster-internal IP
–> Use case: You want your microservice only to be available inside the cluster (Intra cluster communication)
LoadBalancer:
Exposes Service externally using a cloud provider’s load balancer
NodePort:
Exposes Service on each Node’s IP at a static port (the NodePort)
StatefulSet -
Set of Pods with unique, persistent identities and stable hostnames
DaemonSet -
One pod on every node! (for background services)