{
  "id": "redis/sentinel-arbiter-down-failover-delay",
  "signature": "SENTINEL: arbiter node unreachable, failover delayed for 30000ms",
  "signature_zh": "SENTINEL：仲裁节点不可达，故障转移延迟 30000ms",
  "regex": "SENTINEL: arbiter node unreachable, failover delayed for [0-9]+ms",
  "domain": "redis",
  "category": "network_error",
  "subcategory": null,
  "root_cause": "Sentinel's arbiter node is not reachable, preventing the quorum from being reached for failover, causing a delay.",
  "root_cause_type": "generic",
  "root_cause_zh": "Sentinel 的仲裁节点不可达，导致无法达到故障转移所需的法定人数，从而造成延迟。",
  "versions": [
    {
      "version": "6.2.0",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "7.0.0",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "7.2.0",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "Increasing sentinel quorum to 2 to bypass arbiter requirement",
      "why_fails": "This reduces fault tolerance; if the arbiter is down but other nodes are up, failover may still be blocked if quorum is not met.",
      "fail_rate": 0.7,
      "condition": "",
      "sources": []
    },
    {
      "action": "Restarting the arbiter node without checking network connectivity",
      "why_fails": "If the network between Sentinel and arbiter is partitioned, restarting alone won't fix the connectivity issue.",
      "fail_rate": 0.85,
      "condition": "",
      "sources": []
    },
    {
      "action": "Removing the arbiter from the sentinel configuration",
      "why_fails": "This changes the quorum requirement and can lead to split-brain scenarios if the arbiter was intentionally placed there.",
      "fail_rate": 0.8,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Check network connectivity from sentinel to arbiter: 'telnet <arbiter-ip> 26379' and ensure firewall rules allow traffic. If the arbiter is down, restart it and verify it rejoins the quorum: 'redis-cli -p 26379 SENTINEL CKQUORUM <mymaster>'",
      "success_rate": 0.8,
      "how": "Check network connectivity from sentinel to arbiter: 'telnet <arbiter-ip> 26379' and ensure firewall rules allow traffic. If the arbiter is down, restart it and verify it rejoins the quorum: 'redis-cli -p 26379 SENTINEL CKQUORUM <mymaster>'",
      "condition": "",
      "sources": []
    },
    {
      "action": "Temporarily reconfigure sentinel to use a different arbiter or increase the down-after-milliseconds to allow more time for arbiter recovery before failover is triggered",
      "success_rate": 0.7,
      "how": "Temporarily reconfigure sentinel to use a different arbiter or increase the down-after-milliseconds to allow more time for arbiter recovery before failover is triggered",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "Check network connectivity from sentinel to arbiter: 'telnet <arbiter-ip> 26379' and ensure firewall rules allow traffic. If the arbiter is down, restart it and verify it rejoins the quorum: 'redis-cli -p 26379 SENTINEL CKQUORUM <mymaster>'",
    "Temporarily reconfigure sentinel to use a different arbiter or increase the down-after-milliseconds to allow more time for arbiter recovery before failover is triggered"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://redis.io/docs/management/sentinel/",
  "official_doc_section": null,
  "error_code": "SENTINEL",
  "verification_tier": "ai_generated",
  "confidence": 0.84,
  "fix_success_rate": 0.77,
  "resolvable": "partial",
  "first_seen": "2024-01-12",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}