{
  "id": "networking/ipsec-pfs-mismatch",
  "signature": "IPsec: PFS group mismatch in Quick Mode, proposal rejected by peer 203.0.113.5",
  "signature_zh": "IPsec：快速模式中PFS组不匹配，提案被对等体203.0.113.5拒绝",
  "regex": "IPsec: PFS group mismatch in Quick Mode, proposal rejected by peer \\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}",
  "domain": "networking",
  "category": "config_error",
  "subcategory": null,
  "root_cause": "The IKE peer's Perfect Forward Secrecy (PFS) Diffie-Hellman group in Quick Mode does not match the local configuration, causing the SA negotiation to fail.",
  "root_cause_type": "generic",
  "root_cause_zh": "IKE对等体在快速模式中的完美前向保密（PFS）Diffie-Hellman组与本地配置不匹配，导致SA协商失败。",
  "versions": [
    {
      "version": "strongSwan 5.9.11",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "Libreswan 4.12",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "Linux kernel 6.2",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "",
      "why_fails": "The configuration mismatch persists after restart; the PFS group setting must be aligned manually.",
      "fail_rate": 0.95,
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "why_fails": "While this may work, it reduces security and may be rejected by the peer if it requires PFS.",
      "fail_rate": 0.5,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Align PFS groups in ipsec.conf: set pfs=yes and esp=aes256-sha256-modp2048 on both peers, then reload: ipsec reload",
      "success_rate": 0.9,
      "how": "Align PFS groups in ipsec.conf: set pfs=yes and esp=aes256-sha256-modp2048 on both peers, then reload: ipsec reload",
      "condition": "",
      "sources": []
    },
    {
      "action": "Check peer logs for supported groups and update local config accordingly; e.g., on strongSwan use: swanctl --list-sas | grep 'pfs'",
      "success_rate": 0.85,
      "how": "Check peer logs for supported groups and update local config accordingly; e.g., on strongSwan use: swanctl --list-sas | grep 'pfs'",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "Align PFS groups in ipsec.conf: set pfs=yes and esp=aes256-sha256-modp2048 on both peers, then reload: ipsec reload",
    "Check peer logs for supported groups and update local config accordingly; e.g., on strongSwan use: swanctl --list-sas | grep 'pfs'"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://docs.strongswan.org/docs/5.9/config/ipsec-conf.html",
  "official_doc_section": null,
  "error_code": null,
  "verification_tier": "ai_generated",
  "confidence": 0.87,
  "fix_success_rate": 0.88,
  "resolvable": "true",
  "first_seen": "2024-06-10",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}