{
  "status": "shipping",
  "advantages": [],
  "limitations": [],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-11",
  "slug": "asymmetric-namespace-access",
  "term": "Asymmetric Namespace Access",
  "aliases": [
    "ANA",
    "NVMe ANA"
  ],
  "definition": "Asymmetric Namespace Access is the NVMe mechanism for reporting namespace access states through different controllers.",
  "note": "Linux native NVMe multipath prefers an optimized path over a non-optimized path before applying its NUMA, round-robin or queue-depth policy. ANA is distinct from SCSI ALUA. It informs path selection, not application leader election or exclusive write ownership.",
  "related": [
    "nvme",
    "multipath-nvme",
    "multipath-io",
    "alua",
    "io-fencing"
  ],
  "citations": [
    {
      "id": "linux-ana",
      "title": "Linux kernel documentation: Linux NVMe multipath, introduction and policies.",
      "url": "https://docs.kernel.org/admin-guide/nvme-multipath.html",
      "accessed": "2026-10-11"
    },
    {
      "id": "hesela-fencing",
      "title": "Storage fencing: why a lost heartbeat does not stop writes",
      "url": "https://hesela.com/analyses/storage-fencing-stale-writes/",
      "accessed": "2026-10-11"
    }
  ]
}