NFS Services Administrator's Guide

Configuring and Administering NFS
Configuring and Administering AutoFS
Chapter 298
3. The automountd daemon, which automounts file systems when they
are requested by users.
The automount command is invoked at system startup. It reads the
automounter master map to create the initial set of AutoFS mount
points in the internal mount table, /etc/mnttab. The automounted file
systems are not automatically mounted at startup. They are points
under which file systems will be mounted later, when users request
access to them.
When AutoFS receives a request to mount a file system that is not
currently mounted, it calls the automountd daemon, which actually
mounts the requested file system. Once the file system is mounted,
further access does not require any action from the automountd daemon.
Unlike the old automounter, AutoFS mounts file systems at the
configured mount points. It does not maintain its own directory of mount
points with symbolic links into it the way the old automounter does.
The automountd daemon is completely independent from the automount
command. Because of this separation, it is possible to add, delete, or
change automounter map information without having to stop and restart
the automountd daemon.
After system startup, when the AutoFS mount points are set up, you can
modify the set of mount points by modifying the automounter maps and
running the automount command to read them and modify the mount
table accordingly. You do not have to stop and restart AutoFS.
If an automounted file system has been idle for 5 minutes, AutoFS
unmounts it.
For more information on AutoFS, type man 1M automount or man 1M
automountd at the HP-UX prompt.
CAUTION File systems under the management of AutoFS must always be
maintained through AutoFS utilities, automountd and automount.
Manually mounting and unmounting AutoFS managed file systems can
lead to disruptive or unpredictable results, including but not limited to:
commands hanging or not returning expected results, and applications
failing due to their dependencies on these mounted filesystems.