NFS Services Administrator's Guide

Configuring and Administering AutoFS
The -null Map
Chapter 3 141
The -null Map
The -null map is used to ignore mapping entries that do not apply to
your host, but which would otherwise be inherited from NIS or LDAP
maps.
The -null option causes AutoFS to ignore AutoFS map entries that
affect the specified directory. For example, an NIS (or LDAP)
auto_master map is configured such that AutoFS mounts the
auto_home map on /home, as follows:
/home auto_home
You can include the following line in the /etc/auto_master file, before
the +auto_master entry, so that the NIS auto_home map is not used for
the system:
/home -null
+auto_master
NOTE The -null entry must precede the included map entry.
Turning Off an AutoFS Map with the -null Map
To turn off a map using the -null map, follow these steps:
1. Add a line with the following syntax to the AutoFS master map:
local_directory -null
2. If AutoFS is running, enter the following command on each client
that uses the map, to force AutoFS to reread its maps:
/usr/sbin/automount