Redis on k3s¶

Overview¶

Runs Redis for cache, rate limiting, locks, or short-lived queues. On a single-node VPS, deploy one instance with bounded memory; Sentinel or replicas on the same host do not protect against host failure.

GitOps Configuration¶

Use a maintained Redis Helm chart and pin its chart version. A minimal values file should include:

architecture: standalone
auth:
  existingSecret: redis-auth
  existingSecretPasswordKey: password
master:
  persistence:
    enabled: true
    size: 4Gi
  resources:
    requests:
      cpu: 50m
      memory: 128Mi
    limits:
      memory: 512Mi
  configuration: |-
    maxmemory 384mb
    maxmemory-policy allkeys-lru

Choose the eviction policy based on semantics: allkeys-lru is suitable for a cache; use noeviction when silent data eviction is unacceptable. Persistence does not turn Redis into a primary database.

Applications connect through the ClusterIP service, normally redis-master.data.svc.cluster.local:6379. Source the password from the secret manager.

Verification¶

kubectl get pod,pvc,svc -n data
kubectl exec -n data statefulset/redis-master -- redis-cli -a "$REDIS_PASSWORD" PING
kubectl exec -n data statefulset/redis-master -- redis-cli -a "$REDIS_PASSWORD" INFO memory

Monitor used memory, evictions, hit ratio, blocked clients, command latency, and rejected connections.