{
  "id": "cicd/github-actions-connect-timeout",
  "signature": "Error: Failed to connect to github.com port 443: Connection timed out",
  "signature_zh": "错误：无法连接到 github.com 端口 443：连接超时",
  "regex": "Error: Failed to connect to github\\.com port 443: Connection timed out",
  "domain": "cicd",
  "category": "network_error",
  "subcategory": null,
  "root_cause": "GitHub Actions runner cannot reach github.com due to DNS resolution failures, firewall rules, or proxy misconfiguration in the runner environment.",
  "root_cause_type": "generic",
  "root_cause_zh": "GitHub Actions 运行器无法访问 github.com，原因是运行器环境中的 DNS 解析失败、防火墙规则或代理配置错误。",
  "versions": [
    {
      "version": "GitHub Actions Runner 2.308.0",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "Ubuntu 22.04",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "Windows Server 2022",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "Restarting the runner service without checking network connectivity",
      "why_fails": "The underlying network issue persists after restart; runner will hit the same timeout on next job.",
      "fail_rate": 0.95,
      "condition": "",
      "sources": []
    },
    {
      "action": "Adding more retries via workflow configuration (e.g., 'retry-on-error: true')",
      "why_fails": "GitHub Actions retries only the step, not the underlying TCP connection; connection timeout is fatal and not recoverable by retrying the step.",
      "fail_rate": 0.9,
      "condition": "",
      "sources": []
    },
    {
      "action": "Clearing runner cache and reinstalling the runner agent",
      "why_fails": "The runner agent itself is functional; the issue is at the network layer, not the agent software.",
      "fail_rate": 0.85,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Configure proxy environment variables on the runner: export http_proxy=http://proxy.example.com:8080; export https_proxy=http://proxy.example.com:8080; export no_proxy=localhost,127.0.0.1",
      "success_rate": 0.85,
      "how": "Configure proxy environment variables on the runner: export http_proxy=http://proxy.example.com:8080; export https_proxy=http://proxy.example.com:8080; export no_proxy=localhost,127.0.0.1",
      "condition": "",
      "sources": []
    },
    {
      "action": "Update DNS resolver on the runner host: echo 'nameserver 8.8.8.8' > /etc/resolv.conf",
      "success_rate": 0.75,
      "how": "Update DNS resolver on the runner host: echo 'nameserver 8.8.8.8' > /etc/resolv.conf",
      "condition": "",
      "sources": []
    },
    {
      "action": "Check firewall rules to allow outbound HTTPS (port 443) to github.com IP ranges: nslookup github.com; sudo ufw allow out on eth0 to any port 443 proto tcp",
      "success_rate": 0.8,
      "how": "Check firewall rules to allow outbound HTTPS (port 443) to github.com IP ranges: nslookup github.com; sudo ufw allow out on eth0 to any port 443 proto tcp",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "Configure proxy environment variables on the runner: export http_proxy=http://proxy.example.com:8080; export https_proxy=http://proxy.example.com:8080; export no_proxy=localhost,127.0.0.1",
    "Update DNS resolver on the runner host: echo 'nameserver 8.8.8.8' > /etc/resolv.conf",
    "Check firewall rules to allow outbound HTTPS (port 443) to github.com IP ranges: nslookup github.com; sudo ufw allow out on eth0 to any port 443 proto tcp"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://docs.github.com/en/actions/hosting-your-own-runners/managing-self-hosted-runners/about-self-hosted-runners#communication-between-self-hosted-runners-and-github",
  "official_doc_section": null,
  "error_code": "CONNECTION_TIMEOUT",
  "verification_tier": "ai_generated",
  "confidence": 0.85,
  "fix_success_rate": 0.8,
  "resolvable": "true",
  "first_seen": "2023-05-12",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}