8.2. Creating the /etc/fstab File

#### Linux From Scratch - Version 7.10-rc1

### Chapter 8. Making the LFS System Bootable

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# 8.2. Creating the /etc/fstab File

The `/etc/fstab` file is used by some programs to determine where file systems are to be mounted by default, in which order, and which must be checked (for integrity errors) prior to mounting. Create a new file systems table like this:

    cat > /etc/fstab << "EOF"
    # Begin /etc/fstab

    # file system  mount-point  type     options             dump  fsck
    #                                                              order

    /dev/<xxx>     /            <fff>    defaults            1     1
    /dev/<yyy>     swap         swap     pri=1               0     0
    proc           /proc        proc     nosuid,noexec,nodev 0     0
    sysfs          /sys         sysfs    nosuid,noexec,nodev 0     0
    devpts         /dev/pts     devpts   gid=5,mode=620      0     0
    tmpfs          /run         tmpfs    defaults            0     0
    devtmpfs       /dev         devtmpfs mode=0755,nosuid    0     0

    # End /etc/fstab
    EOF

Replace `<xxx>`, `<yyy>`, and `<fff>` with the values appropriate for the system, for example, `sda2`, `sda5`, and `ext4`. For details on the six fields in this file, see man 5 fstab.

Filesystems with MS-DOS or Windows origin (i.e.: vfat, ntfs, smbfs, cifs, iso9660, udf) need the “iocharset” mount option in order for non-ASCII characters in file names to be interpreted properly. The value of this option should be the same as the character set of your locale, adjusted in such a way that the kernel understands it. This works if the relevant character set definition (found under File systems -> Native Language Support) has been compiled into the kernel or built as a module. The “codepage” option is also needed for vfat and smbfs filesystems. It should be set to the codepage number used under MS-DOS in your country. E.g., in order to mount USB flash drives, a ru_RU.KOI8-R user would need the following in the options portion of its mount line in `/etc/fstab`:

    noauto,user,quiet,showexec,iocharset=koi8r,codepage=866

The corresponding options fragment for ru_RU.UTF-8 users is:

    noauto,user,quiet,showexec,iocharset=utf8,codepage=866

### Note

In the latter case, the kernel emits the following message:

    FAT: utf8 is not a recommended IO charset for FAT filesystems,
        filesystem will be case sensitive!

This negative recommendation should be ignored, since all other values of the “iocharset” option result in wrong display of filenames in UTF-8 locales.

It is also possible to specify default codepage and iocharset values for some filesystems during kernel configuration. The relevant parameters are named “Default NLS Option” (`CONFIG_NLS_DEFAULT)`, “Default Remote NLS Option” (`CONFIG_SMB_NLS_DEFAULT`), “Default codepage for FAT” (`CONFIG_FAT_DEFAULT_CODEPAGE`), and “Default iocharset for FAT” (`CONFIG_FAT_DEFAULT_IOCHARSET`). There is no way to specify these settings for the ntfs filesystem at kernel compilation time.

It is possible to make the ext3 filesystem reliable across power failures for some hard disk types. To do this, add the `barrier=1` mount option to the appropriate entry in `/etc/fstab`. To check if the disk drive supports this option, run hdparm on the applicable disk drive. For example, if:

    hdparm -I /dev/sda | grep NCQ

returns non-empty output, the option is supported.

Note: Logical Volume Management (LVM) based partitions cannot use the `barrier` option.

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