{
    "mode": "man",
    "parameter": "blkmapd",
    "section": "8",
    "url": "https://www.chedong.com/phpMan.php/man/blkmapd/8/json",
    "generated": "2026-06-14T04:15:55Z",
    "synopsis": "",
    "sections": {
        "NAME": {
            "content": "blkmapd - pNFS block layout mapping daemon\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "",
            "subsections": [
                {
                    "name": "blkmapd [-h] [-d] [-f]",
                    "content": ""
                }
            ]
        },
        "DESCRIPTION": {
            "content": "The  blkmapd  daemon  performs device discovery and mapping for the parallel NFS (pNFS) block\nlayout client [RFC5663].\n\nThe pNFS block layout protocol builds a complex storage hierarchy from a set of  simple  vol‐\numes.   These  simple  volumes  are  addressed by content, using a signature on the volume to\nuniquely name each one.  The daemon locates a volume by examining each block  device  in  the\nsystem for the given signature.\n\nThe  topology  typically  consists  of a hierarchy of volumes built by striping, slicing, and\nconcatenating the simple volumes.  The blkmapd daemon uses the device-mapper driver  to  con‐\nstruct logical devices that reflect the server topology, and passes these devices to the ker‐\nnel for use by the pNFS block layout client.\n",
            "subsections": []
        },
        "OPTIONS": {
            "content": "",
            "subsections": [
                {
                    "name": "-h",
                    "content": "",
                    "flag": "-h"
                },
                {
                    "name": "-d",
                    "content": "",
                    "flag": "-d"
                },
                {
                    "name": "-f",
                    "content": "",
                    "flag": "-f"
                }
            ]
        },
        "CONFIGURATION FILE": {
            "content": "The blkmapd daemon  recognizes  the  following  value  from  the  [general]  section  of  the\n/etc/nfs.conf configuration file:\n",
            "subsections": [
                {
                    "name": "pipefs-directory",
                    "content": "Tells  blkmapd  where  to  look  for  the rpcpipefs filesystem.  The default value is\n/var/lib/nfs/rpcpipefs.\n"
                }
            ]
        },
        "SEE ALSO": {
            "content": "nfs(5), dmsetup(8), nfs.conf(5)\n\nRFC 5661 for the NFS version 4.1 specification.\nRFC 5663 for the pNFS block layout specification.\n",
            "subsections": []
        },
        "AUTHORS": {
            "content": "Haiying Tang <TangHaiying@emc.com>\nJim Rees <rees@umich.edu>\n\n\n\n11 August 2011                                 blkmapd(8)",
            "subsections": []
        }
    },
    "summary": "blkmapd - pNFS block layout mapping daemon",
    "flags": [
        {
            "flag": "-h",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "-d",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "-f",
            "long": null,
            "arg": null,
            "description": ""
        }
    ],
    "examples": [],
    "see_also": [
        {
            "name": "nfs",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/nfs/5/json"
        },
        {
            "name": "dmsetup",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/dmsetup/8/json"
        },
        {
            "name": "nfs.conf",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/nfs.conf/5/json"
        }
    ]
}