Session affinity (also known as sticky sessions) ensures that requests from the same client are consistently routed to the same backend pod. In Kubernetes, sessionAffinity refers to a mechanism that allows a client to always be redirected to the same pod when the client hits a service.
Enable session affinity by setting service.spec.sessionAffinity to ClientIP:
apiVersion: v1
kind: Service
metadata:
name: wordpress-lsmnl-wordpress
namespace: wordpress-lsmnl
labels:
app: wordpress-lsmnl-wordpress
spec:
type: LoadBalancer
selector:
app: wordpress-lsmnl-wordpress
sessionAffinity: ClientIP
Configure the maximum session sticky time using sessionAffinityConfig:
apiVersion: v1
kind: Service
metadata:
name: my-service
spec:
type: LoadBalancer
sessionAffinity: ClientIP
sessionAffinityConfig:
clientIP:
timeoutSeconds: 10800 # 3 hours
None: No session affinity (default)ClientIP: Route based on client's IP address. All requests from the same client IP will be directed to the same pod.timeoutSeconds: Duration to maintain affinity