<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ <!ENTITY % general-entities SYSTEM "../general.ent"> %general-entities; ]> <sect1 id="ch-bootable-fstab"> <?dbhtml filename="fstab.html"?> <title>Creating the /etc/fstab File</title> <indexterm zone="ch-bootable-fstab"> <primary sortas="e-/etc/fstab">/etc/fstab</primary> </indexterm> <para>The <filename>/etc/fstab</filename> 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:</para> <screen revision="sysv"><userinput>cat > /etc/fstab << "EOF" <literal># Begin /etc/fstab # file system mount-point type options dump fsck # order /dev/<replaceable><xxx></replaceable> / <replaceable><fff></replaceable> defaults 1 1 /dev/<replaceable><yyy></replaceable> 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 tmpfs /dev/shm tmpfs nosuid,nodev 0 0 cgroup2 /sys/fs/cgroup cgroup2 nosuid,noexec,nodev 0 0 # End /etc/fstab</literal> EOF</userinput></screen> <screen revision="systemd"><userinput>cat > /etc/fstab << "EOF" <literal># Begin /etc/fstab # file system mount-point type options dump fsck # order /dev/<replaceable><xxx></replaceable> / <replaceable><fff></replaceable> defaults 1 1 /dev/<replaceable><yyy></replaceable> swap swap pri=1 0 0 # End /etc/fstab</literal> EOF</userinput></screen> <para>Replace <replaceable><xxx></replaceable>, <replaceable><yyy></replaceable>, and <replaceable><fff></replaceable> with the values appropriate for the system, for example, <filename class="partition">sda2</filename>, <filename class="partition">sda5</filename>, and <systemitem class="filesystem">ext4</systemitem>. For details on the six fields in this file, see <ulink role='man' url='&man;fstab.5'>fstab(5)</ulink>.</para> <para>Filesystems with MS-DOS or Windows origin (i.e. vfat, ntfs, smbfs, cifs, iso9660, udf) need a special option, utf8, in order for non-ASCII characters in file names to be interpreted properly. For non-UTF-8 locales, the value of <option>iocharset</option> should be set to be the same as the character set of the 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 when configuring the kernel) has been compiled into the kernel or built as a module. However, if the character set of the locale is UTF-8, the corresponding option <option>iocharset=utf8</option> would make the file system case sensitive. To fix this, use the special option <option>utf8</option> instead of <option>iocharset=utf8</option>, for UTF-8 locales. The <quote>codepage</quote> option is also needed for vfat and smbfs filesystems. It should be set to the codepage number used under MS-DOS in your country. For example, 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 <filename>/etc/fstab</filename>:</para> <screen><literal>noauto,user,quiet,showexec,codepage=866,iocharset=koi8r</literal></screen> <para>The corresponding options fragment for ru_RU.UTF-8 users is:</para> <screen><literal>noauto,user,quiet,showexec,codepage=866,utf8</literal></screen> <para>Note that using <option>iocharset</option> is the default for <literal>iso8859-1</literal> (which keeps the file system case insensitive), and the <option>utf8</option> option tells the kernel to convert the file names using UTF-8 so they can be interpreted in the UTF-8 locale.</para> <!--note> <para>In the latter case, the kernel emits the following message:</para> <screen><computeroutput>FAT: utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive!</computeroutput></screen> <para>This negative recommendation should be ignored, since all other values of the <quote>iocharset</quote> option result in wrong display of filenames in UTF-8 locales.</para> </note--> <para>It is also possible to specify default codepage and iocharset values for some filesystems during kernel configuration. The relevant parameters are named <quote>Default NLS Option</quote> (<option>CONFIG_NLS_DEFAULT)</option>, <quote>Default Remote NLS Option</quote> (<option>CONFIG_SMB_NLS_DEFAULT</option>), <quote>Default codepage for FAT</quote> (<option>CONFIG_FAT_DEFAULT_CODEPAGE</option>), and <quote>Default iocharset for FAT</quote> (<option>CONFIG_FAT_DEFAULT_IOCHARSET</option>). There is no way to specify these settings for the ntfs filesystem at kernel compilation time.</para> <!-- Obsolete since 2011. barrier is the default for both ext3 and ext4. <para>It is possible to make the ext3 filesystem reliable across power failures for some hard disk types. To do this, add the <option>barrier=1</option> mount option to the appropriate entry in <filename>/etc/fstab</filename>. To check if the disk drive supports this option, run <ulink url="&blfs-book;general/hdparm.html">hdparm</ulink> on the applicable disk drive. For example, if:</para> <screen role="nodump"><userinput>hdparm -I /dev/sda | grep NCQ</userinput></screen> <para>returns non-empty output, the option is supported.</para> <para>Note: Logical Volume Management (LVM) based partitions cannot use the <option>barrier</option> option.</para> --> </sect1>