fstab

fstab

During the boot process, file systems listed in /etc/fstab are automatically mounted (unless they are listed with the noauto option).

device       /mount-point fstype     options      dumpfreq     passno

device

A device name (which should exist), as explained in Section 18.2.

mount-point

A directory (which should exist), on which to mount the file system.

fstype

The file system type to pass to mount(8). The default FreeBSD file system is ufs.

options

Either rw for read-write file systems, or ro for read-only file systems, followed by any other options that may be needed. A common option is noauto for file systems not normally mounted during the boot sequence. Other options are listed in the mount(8) manual page.

dumpfreq

This is used by dump(8) to determine which file systems require dumping. If the field is missing, a value of zero is assumed.

passno

This determines the order in which file systems should be checked. File systems that should be skipped should have their passno set to zero. The root file system (which needs to be checked before everything else) should have its passno set to one, and other file systems' passno should be set to values greater than one. If more than one file systems have the same passno then fsck(8) will attempt to check file systems in parallel if possible.

Consult the fstab(5) manual page for more information on the format of the /etc/fstab file and the options it contains.

3.6.2 The mount Command

The mount(8) command is what is ultimately used to mount file systems.

In its most basic form, you use:

# mount device mountpoint

There are plenty of options, as mentioned in the mount(8) manual page, but the most common are:

Mount Options

-a

Mount all the file systems listed in /etc/fstab. Except those marked as “noauto”, excluded by the -t flag, or those that are already mounted.

-d

Do everything except for the actual mount system call. This option is useful in conjunction with the -v flag to determine what mount(8) is actually trying to do.

-f

Force the mount of an unclean file system (dangerous), or forces the revocation of write access when downgrading a file system's mount status from read-write to read-only.

-r

Mount the file system read-only. This is identical to using the ro (rdonly for FreeBSD versions older than 5.2) argument to the -o option.

-t fstype

Mount the given file system as the given file system type, or mount only file systems of the given type, if given the -a option.

“ufs” is the default file system type.

-u

Update mount options on the file system.

-v

Be verbose.

-w

Mount the file system read-write.

The -o option takes a comma-separated list of the options, including the following:

noexec

Do not allow execution of binaries on this file system. This is also a useful security option.

nosuid

Do not interpret setuid or setgid flags on the file system. This is also a useful security option.