FSTAB(5)

NAME
fstab, mtab - static filesystem mounting table, mounted filesystems table

SYNOPSIS
/etc/fstab

/etc/mtab

DESCRIPTION

The /etc/fstab file contains entries for filesystems and disk partitions to mount using the mount(8) command, which is normally invoked by the rc script at boot time. This file is used by various utilities that mount, unmount, check the consistency of, dump, and restore file systems. It is also used by the system itself when locating the swap partition.

The /etc/mtab file contains entries for filesystems currently mounted, and is read by programs using the routines described in getmntent(3). umount (see mount(8)) removes entries from this file.

Each entry consists of a line of the form:

    filesystem directory type options freq pass

filesystem
    is the pathname of a block-special device, or the name of a remote filesystem in host:pathname form.

directory
    is the pathname of the directory on which to mount the filesystem.

type
    is the filesystem type, which can be one of:
        4.3 to mount a block-special device
        nfs to mount an exported NFS filesystem
        swap
            to indicate a swap partition
        ignore
            to have the mount command ignore the current entry (good for noting disk partitions that are not being used)

options
    contains a comma-separated list (no spaces) of mounting options, some of which can be applied to all types of filesystems, and others which only apply to specific types.

    4.3 options:

        quota|noquota
            disk quotas are enforced or not enforced

    nfs options:
        bg|fg
            If the first attempt fails, retry in the background, or, in the foreground
        retry=n
            The number of times to retry the mount operation.
        rsize=n
            Set the read buffer size to n bytes.
        wsize=n
            Set the write buffer size to n bytes.
        timeo=n
            Set the NFS timeout to n tenths of a second.
        retrans=n
            The number of NFS retransmissions.
        port=n
            The server IP port number.
        soft|hard
            Return an error if the server does not respond, or continue the retry request until the server responds.
        intr
            Allow keyboard interrupts on hard mounts.
        secure
            Use a more secure protocol for NFS transactions.
        acregmin=n
            Hold cached attributes for at least n seconds after file modification.
        acregmax=n
            Hold cached attributes for no more than n seconds after file modification.
        acdirmin=n
            Hold cached attributes for at least n seconds after directory update.
        acdirmax=n
            Hold cached attributes for no more than n seconds after directory update.
        actimeo=n
            Set min and max times for regular files and directories to n seconds.

    Common options:

        ro|rw
            mount either read-only or read-write
        suid|nosuid
            setuid execution allowed or disallowed
        grpid
            Create files with BSD semantics for propagation of the group ID. With this option, files inherit the group ID of the directory in which they are created, regardless of the directory's setgid bit.
        noauto
            Do not mount this file system automatically (using mount -a).

freq
    is the interval (in days) between dumps.

pass
    is the fsck(8) pass in which to check the partition. Filesystems with the same pass number are checked simultaneously. Filesystems with pass equal to 0 are not checked.

A pound-sign (#) as the first non-white character indicates a comment line which is ignored by routines that read this file. The order of records in /etc/fstab is important because fsck, mount, and umount process the file sequentially; an entry for a file system must appear after the entry for any file system it is to be mounted on top of.

EXAMPLES
In this example, the /home/user directory is hard mounted read-write over the NFS, along with additional swap space in the form of a mounted swap file (see for details on adding swap space):
    /dev/hp0a / 4.3 rw,noquota 1 1
    /dev/hp0b /usr 4.3 rw,noquota 1 1
    example:/home/user /home/user nfs rw,hard,fg 0 0
    /export/swap/myswap swap swap rw 0 0

FILES
/etc/fstab
/etc/mtab

SEE ALSO
getmntent(3), fsck(8), mount(8), quotacheck(8), quotaon(8),