{
    "mode": "man",
    "parameter": "HD",
    "section": "4",
    "url": "https://www.chedong.com/phpMan.php/man/HD/4/json",
    "generated": "2026-06-16T22:26:41Z",
    "sections": {
        "NAME": {
            "content": "hd - MFM/IDE hard disk devices\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "The hd* devices are block devices to access MFM/IDE hard disk drives in raw mode.  The master\ndrive on the primary IDE controller (major device number 3) is hda; the slave drive  is  hdb.\nThe  master  drive  of the second controller (major device number 22) is hdc and the slave is\nhdd.\n\nGeneral IDE block device names have the form hdX, or hdXP, where X is a letter  denoting  the\nphysical  drive,  and P is a number denoting the partition on that physical drive.  The first\nform, hdX, is used to address the whole drive.  Partition numbers are assigned in  the  order\nthe  partitions are discovered, and only nonempty, nonextended partitions get a number.  How‐\never, partition numbers 1–4 are given to the four partitions described in the MBR (the  \"pri‐\nmary\"  partitions), regardless of whether they are unused or extended.  Thus, the first logi‐\ncal partition will be hdX5.  Both DOS-type partitioning and  BSD-disklabel  partitioning  are\nsupported.  You can have at most 63 partitions on an IDE disk.\n\nFor  example,  /dev/hda  refers  to  all  of the first IDE drive in the system; and /dev/hdb3\nrefers to the third DOS \"primary\" partition on the second one.\n\nThey are typically created by:\n\nmknod -m 660 /dev/hda b 3 0\nmknod -m 660 /dev/hda1 b 3 1\nmknod -m 660 /dev/hda2 b 3 2\n...\nmknod -m 660 /dev/hda8 b 3 8\nmknod -m 660 /dev/hdb b 3 64\nmknod -m 660 /dev/hdb1 b 3 65\nmknod -m 660 /dev/hdb2 b 3 66\n...\nmknod -m 660 /dev/hdb8 b 3 72\nchown root:disk /dev/hd*\n",
            "subsections": []
        },
        "FILES": {
            "content": "/dev/hd*\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "chown(1), mknod(1), sd(4), mount(8)\n",
            "subsections": []
        },
        "COLOPHON": {
            "content": "This page is part of release 5.10 of the Linux  man-pages  project.   A  description  of  the\nproject,  information about reporting bugs, and the latest version of this page, can be found\nat https://www.kernel.org/doc/man-pages/.\n\n\n\nLinux                                        2017-09-15                                        HD(4)",
            "subsections": []
        }
    },
    "summary": "hd - MFM/IDE hard disk devices",
    "flags": [],
    "examples": [],
    "see_also": [
        {
            "name": "chown",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/chown/1/json"
        },
        {
            "name": "mknod",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/mknod/1/json"
        },
        {
            "name": "sd",
            "section": "4",
            "url": "https://www.chedong.com/phpMan.php/man/sd/4/json"
        },
        {
            "name": "mount",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/mount/8/json"
        }
    ]
}