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Nerve Centre KPIs · Audit Profile · Sentiment Settings Redis-specific health audit. Answers six questions: (1) is access locked down to an ACL user with least-privilege stats permissions and is TLS on for cloud-managed instances; (2) is the instance reachable and accepting connections, or are clients being rejected at maxclients; (3) is command latency healthy and is the SLOWLOG quiet, or are large keys / slow Lua scripts dragging p95; (4) are replicas connected and caught up, and in Cluster mode are all 16384 slots covered with master plus replica; (5) is memory pressure under control - used_memory clear of maxmemory and eviction not storming; (6) is persistence healthy and an offsite backup recent enough to meet recovery objectives. Cross-channel area joins Redis load and slow commands to commerce-sibling checkout windows to size live revenue at risk.

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What this audit checks

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Authentication & access

  • AUTH succeeds with the configured ACL user (Redis 6+); ‘default’ user not relied on in production
  • Stats user has only +info +client +cluster +readonly - no write or admin grants
  • TLS enabled (rediss://) for cloud-managed instances (ElastiCache / Redis Cloud / Upstash)
  • Sentinel / Cluster endpoint reachable so shards can be enumerated via CLUSTER NODES

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Connection & availability

  • INFO server responds and uptime_in_seconds confirms no recent unplanned restart
  • rejected_connections from INFO stats is 0 over 24h - no clients refused at maxclients
  • connected_clients / maxclients (pool saturation) below 90%
  • blocked_clients on BLPOP / BRPOP / WAIT not sustained above the alert band

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Query performance (p95 / slow queries)

  • Command latency p95 below 10ms (Redis commands are typically sub-ms)
  • Command latency p99 below 50ms - spikes point to large keys, slow Lua, or swap
  • SLOWLOG GET 128 entries under the 15m alert band (default slowlog-log-slower-than 10ms)
  • Top SLOWLOG command patterns reviewed - no O(N) KEYS / SMEMBERS / HGETALL on hot keys

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Replication & lag

  • connected_slaves from INFO replication is at least 1 (failover target available)
  • Replica master_last_io_seconds_ago (lag) below 10s on every replica
  • Replica state STREAMING - not RECOVERING, BROKEN, or STOPPED
  • Cluster mode: cluster_slots_ok = 16384 from CLUSTER INFO - no slot left uncovered

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Storage & capacity

  • used_memory / maxmemory below 90% - clear of the eviction threshold
  • evicted_keys delta below 100/min sustained (maxmemory pressure indicator)
  • mem_fragmentation_ratio between 1.0 and 1.5 - below 1.0 means swap in progress (bad)
  • Total keys per db growing in line with expectation - no silent key explosion

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Backups & durability

  • rdb_last_save_time from INFO persistence within the last 60 minutes
  • aof_last_bgrewrite_status from INFO persistence is ‘ok’, not ‘err’
  • Last successful RDB / AOF backup shipped offsite within 72h (ElastiCache: CloudWatch backup events)

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Cross-channel: revenue protection

  • Redis ops/sec spike with no matching ecom order spike (sibling = bigcommerce/shopify.orders_per_15m) - cache stampede or bot
  • Connected-clients saturation above 90% maxclients during a sibling traffic burst (drops downstream services)
  • Session-key count drift vs active ecom sessions (redis.keyspace prefix=‘session:*’ vs sibling.checkout active sessions)
  • SLOWLOG entries co-occurring with a sibling checkout-completion drop within a 5m window

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Severity thresholds

SignalWarnCritical
connection_error_rate15
query_p95_ms1050
replication_lag_sec1030
disk_usage_pct8090
slow_query_count1050

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Data sources

  • GET redis://{host}:{port}/{db} INFO server - Instance identity, version, uptime_in_seconds
  • GET redis://{host}:{port}/{db} INFO clients - connected_clients, blocked_clients, maxclients
  • GET redis://{host}:{port}/{db} INFO stats - ops/sec, keyspace_hits/misses, evicted_keys, rejected_connections
  • GET redis://{host}:{port}/{db} INFO memory - used_memory, maxmemory, mem_fragmentation_ratio
  • GET redis://{host}:{port}/{db} INFO replication - connected_slaves, master_last_io_seconds_ago, role
  • GET redis://{host}:{port}/{db} INFO persistence - rdb_last_save_time, aof_last_bgrewrite_status
  • GET redis://{host}:{port}/{db} SLOWLOG GET 128 - Recent slow commands with duration and pattern
  • GET redis://{host}:{port}/{db} CLUSTER INFO - cluster_slots_ok / cluster_state (Cluster only)
  • GET redis://{host}:{port}/{db} CLUSTER NODES - Per-node role and slot ownership (Cluster only)