Automate Mounting of File Systems

Introduction to Autofs

The autofs package contains userspace tools that work with the kernel to mount and un-mount removable file systems. This is useful for allowing users to mount floppies, cdroms and other removable storage devices without requiring the system administrator to mount the devices. This may not be ideal for all installations, so be aware of the risks before implementing this feature.

Package Information

Additional Downloads

User Notes: http://wiki.linuxfromscratch.org/blfs/wiki/autofs

Kernel Configuration

Verify that kernel support has been compiled in or built as modules in the following areas:

File systems ⇒
    Kernel automounter version 4 support  Y or M
    Network File Systems ⇒
        NFS file system support     Y or M (optional)
        SMB file system support     Y or M (optional)

Recompile and install the new kernel, if necessary.

Installation of Autofs

Install autofs by running the following commands:

patch -Np1 -i ../autofs-4.1.4-consolidated-1.patch &&
./configure --prefix=/ --mandir=/usr/share/man &&
make

Now, as the root user:

make install &&
rm /etc/rc.d/init.d/autofs

Command Explanations

patch -Np1 -i ../autofs-4.1.4-consolidated-1.patch: This patch is a consolidation of nine small patches available at http://ftp.kernel.org/pub/linux/daemons/autofs/v4/. The patches can be applied individually if desired.

rm /etc/rc.d/init.d/autofs: This command removes the installed script which only works on specific distributions.

Configuring Autofs

Config Files

/etc/sysconfig/autofs.conf, /etc/auto.master, /etc/auto.misc, and /etc/auto.net

Configuration Information

The installation process creates auto.master, auto.misc and auto.net. You will replace the auto.master with the following commands:

mv /etc/auto.master /etc/auto.master.bak &&
cat > /etc/auto.master << "EOF"
# Begin /etc/auto.master

/media  /etc/auto.misc

# End /etc/auto.master
EOF
[Note]

Note

This file mounts a new media directory over the one created by LFS and will therefore hide any mounts made by the fstab file into that directory.

While this package could be used to mount NFS shares and SMB shares, that feature is not configured in these instructions. NFS shares are covered on the next page.

The auto.misc must be configured to your working hardware. The loaded configuration file should load your cdrom if /dev/cdrom is active or it can be edited to match your device setup and examples for floppies are available in the file and easily activated. Documentation for this file is available using the man 5 autofs command.

Boot Script

Install the /etc/rc.d/init.d/autofs mount script and /etc/sysconfig/autofs.conf support file included with the blfs-bootscripts-20060910 package.

make install-autofs

The time-out variable is set in /etc/sysconfig/autofs.conf. The installed file sets a default of 60 seconds of inactivity before unmounting the device. A much shorter time may be necessary to protect buffer writing to a floppy if users tend to remove the media prior to the timeout setting.

Contents

Installed Program: automount
Installed Libraries: autofs modules
Installed Directories: /lib/autofs and /var/run/autofs

Short Descriptions

automount

is the daemon that performs the mounting when a request is made for the device.

Last updated on 2007-01-18 13:38:19 -0600