{
  "slug": "nearline-hdd",
  "term": "Nearline HDD",
  "aliases": [
    "capacity HDD",
    "archive disk"
  ],
  "definition": "A class of high-capacity, lower-RPM hard drives intended for always-on but not primary-tier storage.",
  "note": "In contemporary vendor language, “nearline” means high-capacity enterprise HDDs kept online for bulk cloud object, analytics, and backup-target tiers—typically 7200 RPM 3.5-inch SATA or SAS drives with enterprise duty-cycle and vibration specs—not low-latency transactional spindles. Recording tech on these lines adopts density tools first (helium, SMR, HAMR, MAMR). The word historically also meant automated tape/optical “near online” libraries in IBM-era usage; do not confuse marketing nearline HDD with that older library sense. Nearline is a product class and workload target, not a single recording mode.",
  "status": "shipping",
  "advantages": [
    {
      "text": "Lowest cost per terabyte among spinning disk offerings for warm/cold data.",
      "citationIds": [
        "c1"
      ]
    }
  ],
  "limitations": [],
  "related": [
    "hdd",
    "helium-hdd",
    "smr",
    "cmr",
    "hamr",
    "hot-warm-cold"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "citations": [
    {
      "id": "c1",
      "title": "Nearline storage",
      "url": "https://en.wikipedia.org/wiki/Nearline_storage",
      "accessed": "2026-03-26"
    },
    {
      "id": "n2",
      "title": "Seagate — Exos enterprise / mass capacity HDD family",
      "url": "https://www.seagate.com/products/enterprise-drives/exos/",
      "accessed": "2026-10-07"
    },
    {
      "id": "n3",
      "title": "Toshiba — MG09 nearline enterprise capacity HDD",
      "url": "https://storage.toshiba.com/enterprise-hdd/cloud-scale-capacity/mg09-series",
      "accessed": "2026-10-07"
    }
  ]
}