Builds the target 3-node raw StatefulSet alongside the legacy Bitnami Helm
release so data can migrate via REPLICAOF during a future short maintenance
window (Phase 3-7). No traffic touches the new cluster yet — HAProxy still
points at redis-node-{0,1}.
Architecture:
- 3 redis pods, each co-locating redis + sentinel + oliver006/redis_exporter
- podManagementPolicy=Parallel + init container that writes fresh
sentinel.conf on every boot by probing peer sentinels and redis for
consensus master (priority: sentinel vote > role:master with slaves >
pod-0 fallback). Kills the stale-state bug that broke sentinel on Apr 19 PM.
- redis.conf `include /shared/replica.conf` — init container writes
`replicaof <master> 6379` for non-master pods so they come up already in
the correct role. No bootstrap race.
- master+replica memory 768Mi (was 512Mi) for concurrent BGSAVE+AOF fork
COW headroom. auto-aof-rewrite-percentage=200 tunes down rewrite churn.
- RDB (save 900 1 / 300 100 / 60 10000) + AOF appendfsync=everysec.
- PodDisruptionBudget minAvailable=2.
Also:
- HAProxy scaled 2→3 replicas + PodDisruptionBudget minAvailable=2, since
Phase 6 drops Nextcloud's sentinel-query fallback and HAProxy becomes
the sole client-facing path for all 17 consumers.
- New Prometheus alerts: RedisMemoryPressure, RedisEvictions,
RedisReplicationLagHigh, RedisForkLatencyHigh, RedisAOFRewriteLong,
RedisReplicasMissing. Updated RedisDown to cover both statefulsets
during the migration.
- databases.md updated to describe the interim parallel-cluster state.
Verified live: redis-v2-0 master, redis-v2-{1,2} replicas, master_link_status
up, all 3 sentinels agree on get-master-addr-by-name. All new alerts loaded
into Prometheus and inactive.
Beads: code-v2b (still in progress — Phase 3-7 await maintenance window).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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