Red Hat LINUX 7.2 Reference Manual page 292

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stops in designated runlevels, the mount configurations in the various files can be automatically im-
plemented. In order to use autofs, you must have the autofs RPM installed on your system.
The autofs configuration files are arranged in a parent-child relationship. A main configuration file
(/etc/auto.master) refers mount points on your system that are linked to a particular map type,
which take the form of other configuration files, programs, NIS maps, and other less common mount
methods. The auto.master file contains lines referring to each of these mount points, organized
like this:
<mount-point>
The <mount-point> indicates where the device or exported filesystem should mount on your local
filesystem. The <map-type> relates to the way in which the mount point will be mounted. The
most common method for auto mounting NFS exports is to use a file as the map type for the particular
mount point. The map file, usually named auto. <mount-point> , where <mount-point> is
the mount point designated in auto.master, contains lines that look like this:
<directory>
The <directory> refers to the directory within the mount point where the exported filesystem
should be mounted. Much like a standard mount command, the host exporting the filesystem, as
well as the fil esystem being exported, are required in the <host> : <exported-filesystem>
section. To specify particular options to be used when mounting the exported filesystem, place them
in the <mount-options> section, separated by commas. For NFS mounts that use autofs, you
should definitely place -fstype=nfs in the <mount-options> section, at a minimum.
While autofs configuration files can be used for a variety of mounts to many types of devices
and filesystems, they are particularly useful in creating NFS mounts. For example, some organi-
zations store a user's /home directory on a central server via an NFS share. Then, they configure
the auto.master file on each of the workstations to point to an auto.home file containing the
specifics for how to mount the /home directory via NFS. This allows the user to access personal data
and configuration files in their /home directory by logging in anywhere on the internal network. The
auto.master file in this situation would look similar to this:
/home
This sets up the /home mount point on the local system to be configured by the /etc/auto.home
file, which may look similar to this:
* -fstype=nfs,soft,intr,rsize=8192,wsize=8192,nosuid
This line states that any directory a user tries to access under the local /home directory (due to the
asterisk character) should result in an NFS mount on the server.domain.com system within its exported
/home filesystem. The mount options specify that each /home directory NFS mounts should use a
particular collection of settings. For more information on mount options, including the ones used in
this example, see Section 17.3.3, Common NFS Mount Options.
<map-type>
<mount-options>
/etc/auto.home
Chapter 17:Network File System (NFS)
<host> : <exported-filesystem>
server.domain.com:/home/&