{
    "mode": "man",
    "parameter": "E2MMPSTATUS",
    "section": "8",
    "url": "https://www.chedong.com/phpMan.php/man/E2MMPSTATUS/8/json",
    "generated": "2026-06-14T13:16:05Z",
    "synopsis": "e2mmpstatus [-i] <filesystem>",
    "sections": {
        "NAME": {
            "content": "e2mmpstatus - Check MMP status of an ext4 file system\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "e2mmpstatus [-i] <filesystem>\n",
            "subsections": []
        },
        "OPTIONS": {
            "content": "",
            "subsections": [
                {
                    "name": "-i",
                    "content": "",
                    "flag": "-i"
                }
            ]
        },
        "DESCRIPTION": {
            "content": "e2mmpstatus  is  used  to check Multiple-Mount Protection (MMP) status of an ext4 file system\nwith the mmp feature enabled.   The  specified  file  system  can  be  a  device  name  (e.g.\n/dev/hdc1,   /dev/sdb2),   or   an   ext4   file   system   label   or   UUID,   for  example\nUUID=8868abf6-88c5-4a83-98b8-bfc24057f7bd or LABEL=root.  By default, the e2mmpstatus program\nchecks  whether  it  is  safe to mount the file system without taking the risk of mounting it\nmore than once.\n\nMMP (multiple-mount protection) is a feature that adds protection against the file system be‐\ning  modified  simultaneously  by  more than one node.  It is NOT safe to mount a file system\nwhen one of the following conditions is true:\n1. e2fsck is running on the file system.\n2. the file system is in use by another node.\n3. The MMP block is corrupted or cannot be read for some reason.\nThe e2mmpstatus program might wait for some time to see whether the MMP block  is  being  up‐\ndated by any node during this period.  The time taken depends on how frequently the MMP block\nis being written by the other node.\n",
            "subsections": []
        },
        "EXIT CODE": {
            "content": "The exit code returned by e2mmpstatus is 0 when it is safe to mount the file system,  1  when\nthe MMP block shows the file system is in use on another node and it is NOT safe to mount the\nfile system, and 2 if some other failure occurred that prevents the check from  properly  de‐\ntecting the current MMP status.\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "dumpe2fs(8), e2fsck(8), fstab(5), fsck(8),\n\n\n\nE2fsprogs version 1.46.5                    December 2021                             E2MMPSTATUS(8)",
            "subsections": []
        }
    },
    "summary": "e2mmpstatus - Check MMP status of an ext4 file system",
    "flags": [
        {
            "flag": "-i",
            "long": null,
            "arg": null,
            "description": ""
        }
    ],
    "examples": [],
    "see_also": [
        {
            "name": "dumpe2fs",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/dumpe2fs/8/json"
        },
        {
            "name": "e2fsck",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/e2fsck/8/json"
        },
        {
            "name": "fstab",
            "section": "5",
            "url": "https://www.chedong.com/phpMan.php/man/fstab/5/json"
        },
        {
            "name": "fsck",
            "section": "8",
            "url": "https://www.chedong.com/phpMan.php/man/fsck/8/json"
        }
    ]
}