{
    "content": [
        {
            "type": "text",
            "text": "# BTRFS-SELECT-SUPER (man)\n\n## NAME\n\nbtrfs-select-super - overwrite primary superblock with a backup copy\n\n## SYNOPSIS\n\nbtrfs-select-super -s number <device>\n\n## DESCRIPTION\n\nDestructively overwrite all copies of the superblock with a specified copy. This helps in\ncertain cases, for example when write barriers were disabled during a power failure and not\nall superblocks were written, or if the primary superblock is damaged, eg. accidentally\noverwritten.\n\n## Sections\n\n- **NAME**\n- **SYNOPSIS**\n- **DESCRIPTION**\n- **OPTIONS**\n- **SEE ALSO**\n\nUse structuredContent.sections for detailed options, examples, and full documentation.\n"
        }
    ],
    "structuredContent": {
        "command": "BTRFS-SELECT-SUPER",
        "section": "",
        "mode": "man",
        "summary": "btrfs-select-super - overwrite primary superblock with a backup copy",
        "synopsis": "btrfs-select-super -s number <device>",
        "tldr_summary": null,
        "tldr_examples": [],
        "tldr_source": null,
        "flags": [],
        "examples": [],
        "see_also": [
            {
                "name": "btrfs-inspect-internal",
                "section": "8",
                "url": "https://www.chedong.com/phpMan.php/man/btrfs-inspect-internal/8/json"
            },
            {
                "name": "check",
                "section": "8",
                "url": "https://www.chedong.com/phpMan.php/man/check/8/json"
            }
        ],
        "section_outline": [
            {
                "name": "NAME",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "SYNOPSIS",
                "lines": 2,
                "subsections": []
            },
            {
                "name": "DESCRIPTION",
                "lines": 26,
                "subsections": []
            },
            {
                "name": "OPTIONS",
                "lines": 4,
                "subsections": []
            },
            {
                "name": "SEE ALSO",
                "lines": 5,
                "subsections": []
            }
        ],
        "sections": {
            "NAME": {
                "content": "btrfs-select-super - overwrite primary superblock with a backup copy\n",
                "subsections": []
            },
            "SYNOPSIS": {
                "content": "btrfs-select-super -s number <device>\n",
                "subsections": []
            },
            "DESCRIPTION": {
                "content": "Destructively overwrite all copies of the superblock with a specified copy. This helps in\ncertain cases, for example when write barriers were disabled during a power failure and not\nall superblocks were written, or if the primary superblock is damaged, eg. accidentally\noverwritten.\n\nThe filesystem specified by device must not be mounted.\n\nNote\nPrior to overwriting the primary superblock, please make sure that the backup copies are\nvalid!\n\nTo dump a superblock use the btrfs inspect-internal dump-super command.\n\nThen run the check (in the non-repair mode) using the command btrfs check -s where -s\nspecifies the superblock copy to use.\n\nSuperblock copies exist in the following offsets on the device:\n\n•   primary: 64KiB (65536)\n\n•   1st copy: 64MiB (67108864)\n\n•   2nd copy: 256GiB (274877906944)\n\nA superblock size is 4KiB (4096).\n",
                "subsections": []
            },
            "OPTIONS": {
                "content": "-s|--super <superblock>\nuse 'superblock’th superblock copy, valid values are 0 1 or 2 if the respective\nsuperblock offset is within the device size\n",
                "subsections": []
            },
            "SEE ALSO": {
                "content": "btrfs-inspect-internal(8), btrfsck check(8)\n\n\n\nBtrfs v5.16.2                                02/16/2022                        BTRFS-SELECT-SUPER(8)",
                "subsections": []
            }
        }
    }
}