openova/platform/valkey

Valkey

Redis-compatible in-memory cache. Application Blueprint (see docs/PLATFORM-TECH-STACK.md §4.1 — Data services).

Important: Valkey is NOT a Catalyst control-plane component. The Catalyst control plane uses NATS JetStream KV for its own pub/sub + KV needs (see docs/ARCHITECTURE.md §5 and docs/GLOSSARY.md — event-spine). Valkey is purely an Application-tier cache for Apps that want Redis-compatible caching. The same upstream technology can serve in multiple categories (per PLATFORM-TECH-STACK §1) — Valkey is on the Application side of that split.

Replication via REPLICAOF (per Application's choice; see docs/SRE.md §2.5).

Status: Accepted | Updated: 2026-04-27

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Overview

Valkey provides in-memory caching for sessions, rate limiting, and ephemeral data with multi-region replication support.

As an OSS support provider, OpenOva requires truly open-source components:

• Redis OSS: RSALv2 + SSPL license (since March 2024) - not open source
• Dragonfly: BSL 1.1 license - not open source
• Valkey: BSD-3 license - truly open source

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Why Valkey

Factor	Valkey
License	BSD-3 (truly open source)
Governance	Linux Foundation
Backing	AWS, Google, Oracle, Ericsson, Snap
Origin	Fork of Redis 7.2.4
Compatibility	100% Redis API compatible
DR Strategy	REPLICAOF (same as Redis)

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Architecture

Single Region

flowchart TB
    subgraph Cluster["Valkey Cluster"]
        VK1[Valkey 1]
        VK2[Valkey 2]
        VK3[Valkey 3]
    end

    App[Applications] --> VK1
    App --> VK2
    App --> VK3

Multi-Region DR

flowchart TB
    subgraph Region1["Region 1 (Primary)"]
        VK1[Valkey Primary]
    end

    subgraph Region2["Region 2 (DR)"]
        VK2[Valkey Replica]
    end

    VK1 -->|"REPLICAOF"| VK2
    App1[Apps R1] --> VK1
    App2[Apps R2] --> VK2

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DR Strategy: REPLICAOF

Valkey supports Redis REPLICAOF for async replication:

# On DR region Valkey
REPLICAOF valkey.<env>.<sovereign-domain> 6379

# Promote DR to primary (failover)
REPLICAOF NO ONE

Aspect	Value
Replication	Asynchronous
Lag	Milliseconds to seconds
Consistency	Eventual
Failover	Manual promotion

---

Configuration

Primary Region

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: valkey
  namespace: databases
spec:
  replicas: 1
  template:
    spec:
      containers:
        - name: valkey
          image: valkey/valkey:8-alpine
          args:
            - --requirepass
            - $(VALKEY_PASSWORD)
            - --maxmemory
            - 2gb
          ports:
            - containerPort: 6379
          env:
            - name: VALKEY_PASSWORD
              valueFrom:
                secretKeyRef:
                  name: valkey-credentials
                  key: password

DR Region (Replica)

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: valkey
  namespace: databases
spec:
  replicas: 1
  template:
    spec:
      containers:
        - name: valkey
          image: valkey/valkey:8-alpine
          args:
            - --requirepass
            - $(VALKEY_PASSWORD)
            - --maxmemory
            - 2gb
            - --replicaof
            - valkey.<env>.<sovereign-domain>
            - "6379"
            - --masterauth
            - $(MASTER_PASSWORD)

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Use Cases

Use Case	TTL	Eviction	DR Needed
Session cache	24h	LRU	Yes
Rate limiting	1m	Fixed	No (local)
API cache	5m	LRU	Optional
Feature flags	1m	LRU	Yes

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Monitoring

Metric	Description
valkey_connected_replicas	Number of connected replicas
valkey_replication_lag	Replication lag in bytes
valkey_used_memory	Memory usage
valkey_commands_processed_total	Total commands processed

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Migration from Redis/Dragonfly

Valkey is a drop-in replacement:

1. No application changes - Same Redis protocol
2. Same client libraries - Redis clients work unchanged
3. Same commands - Full Redis command compatibility
4. Same REPLICAOF - Identical DR pattern

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Part of OpenOva