High Availability

Overview

Proxy Hopper is stateless beyond its IP pool state. With Redis as the backend, multiple replicas share a single pool — each IP is checked out to exactly one replica at a time via Redis BLPOP atomicity. This makes horizontal scaling straightforward.

HorizontalPodAutoscaler

autoscaling:
  enabled: true
  minReplicas: 2
  maxReplicas: 10
  targetCPUUtilizationPercentage: 80

HPA with multiple replicas requires the Redis backend. The in-memory backend gives each pod its own independent pool state — IPs may be used concurrently across pods and quarantine state is not shared.

Redis for HA

Use a managed Redis service for production rather than the bundled Bitnami subchart:

backend:
  type: redis
  redis:
    url: redis://my-managed-redis:6379/0

redis:
  enabled: false   # disable bundled subchart

Managed Redis options:

AWS — ElastiCache for Redis
GCP — Cloud Memorystore
Azure — Azure Cache for Redis
Self-hosted — Redis Sentinel or Redis Cluster with persistence enabled

PodDisruptionBudget

Maintain minimum availability during node drain and rolling upgrades:

apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: proxy-hopper
  namespace: proxy-hopper
spec:
  minAvailable: 1
  selector:
    matchLabels:
      app.kubernetes.io/name: proxy-hopper

The Helm chart does not create a PDB automatically — apply this separately.

Resource requests and limits

Proxy Hopper is I/O-bound. CPU usage is low; memory scales with the number of open connections.

resources:
  requests:
    cpu: 100m
    memory: 128Mi
  limits:
    cpu: 500m
    memory: 256Mi

Start conservative and adjust based on observed usage (kubectl top pods).

Health probes

Proxy Hopper exposes readiness and liveness endpoints. The Helm chart configures these automatically, but if you are deploying manually:

livenessProbe:
  httpGet:
    path: /health
    port: admin   # admin API port (default 8081)
  initialDelaySeconds: 5
  periodSeconds: 10

readinessProbe:
  httpGet:
    path: /health
    port: admin
  initialDelaySeconds: 3
  periodSeconds: 5

The admin API must be enabled for health endpoints to be available:

admin:
  enabled: true
  port: 8081

Example: full HA values file

replicaCount: 2

autoscaling:
  enabled: true
  minReplicas: 2
  maxReplicas: 10
  targetCPUUtilizationPercentage: 80

backend:
  type: redis
  redis:
    url: redis://my-managed-redis:6379/0

redis:
  enabled: false

resources:
  requests:
    cpu: 100m
    memory: 128Mi
  limits:
    cpu: 500m
    memory: 256Mi

admin:
  enabled: true
  port: 8081

config:
  existingSecret: proxy-hopper-config

ingress:
  enabled: true
  className: nginx
  hosts:
    - host: proxy-hopper.example.com
      paths:
        - path: /
          pathType: Prefix

Production checklist

Use a Secret for config with auth

If auth is enabled, store the config in a Kubernetes Secret and reference it with config.existingSecret. Credentials in config.inline end up in Helm release history.

Use managed Redis

The bundled Redis subchart is convenient for development but not hardened for production. Use a managed service with persistence and replication enabled.

Set resource requests and limits

Without resource limits, a traffic spike can starve other pods on the node. Set limits based on observed memory usage under load.

Add a PodDisruptionBudget

Ensure at least one replica remains available during node maintenance or rolling upgrades.

Enable the admin API for health checks

The /health endpoint on the admin port is the most reliable liveness/readiness signal. Enable admin.enabled: true in your values.

Getting Started

Concepts

For Administrators

For Developers

For Contributors

Overview

HorizontalPodAutoscaler

Redis for HA

PodDisruptionBudget

Resource requests and limits

Health probes

Example: full HA values file

Production checklist

​Overview

​HorizontalPodAutoscaler

​Redis for HA

​PodDisruptionBudget

​Resource requests and limits

​Health probes

​Example: full HA values file

​Production checklist

Overview

HorizontalPodAutoscaler

Redis for HA

PodDisruptionBudget

Resource requests and limits

Health probes

Example: full HA values file

Production checklist