{
  "slug": "nas-gateway",
  "term": "NAS gateway",
  "aliases": [
    "network-attached storage gateway"
  ],
  "definition": "A NAS gateway is a file-serving system that provides network file access to storage supplied by a separate storage system.",
  "note": "Clients send file requests to the gateway; its storage-facing interface accesses the backing devices. SNIA's 2007 example uses IP file I/O on one side and Fibre Channel block I/O on the other. This separates the file-service layer from the external storage array. [snia-gateway]\n\nImplementation: TR-3461 (May 2019) describes platforms providing CIFS or NFS services using third-party array LUNs as backing storage. The documented platforms could use native disk shelves as well as externally supplied array LUNs, and could expose block protocols too. [flexarray-2019]\n\nTerminology: Gateway identifies the relationship to backing storage; unified storage identifies the access interfaces offered. These describe different architectural properties and can coexist in one system. [snia-gateway] [flexarray-2019]\n\nAccess control: In TR-3461 (May 2019), a FlexArray or V-Series system is itself a host from the backing array's perspective. Array-side LUN masking selects which hosts can access which LUNs; switch zoning controls a different layer. The guide recommends both zoning and host groups for these configurations. [flexarray-2019] File-service permissions do not replace this backing-storage access policy.",
  "status": "shipping",
  "advantages": [],
  "limitations": [
    {
      "text": "The gateway label does not establish support for every external array, path configuration or host protocol.",
      "citationIds": [
        "flexarray-2019"
      ]
    }
  ],
  "related": [
    "nas",
    "san",
    "storage-array",
    "unified-storage",
    "file-storage",
    "block-storage",
    "nfs-storage",
    "smb-protocol"
  ],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "citations": [
    {
      "id": "snia-gateway",
      "title": "SNIA IP Storage whitepaper (2007), printed p. 6: NAS gateway file I/O and external block storage.",
      "url": "https://www.snia.org/sites/default/files/IPSFWhitepaperOct07.pdf",
      "accessed": "2026-10-31"
    },
    {
      "id": "flexarray-2019",
      "title": "Michael Peppers, NetApp TR-3461, May 2019: sections 1-2 (p. 5), gateway services; section 11 (p. 15), array-side LUN masking and zoning.",
      "url": "https://www.netapp.com/media/17184-tr3461.pdf",
      "accessed": "2026-10-31"
    }
  ],
  "updated": "2026-10-31",
  "provenance": [
    "The 2007 SNIA paper explains a file/block architecture, not a requirement for every gateway implementation. [snia-gateway]",
    "The May 2019 NetApp FlexArray/V-Series guide is a historical configuration example, not current product-support or interoperability evidence. [flexarray-2019]",
    "The gateway/unified-storage distinction is editorial synthesis of architectural role and interface coverage, not a measured performance or availability result.",
    "The file-service versus backing-storage access-control distinction is an editorial inference from the documented architecture, not an operational security test or a complete configuration procedure."
  ]
}