Enhanced AutoFS Administrator's Guide

Conﬁguring and Administering AutoFS

Automounting All Exported Directories Using the -hosts Map

Chapter 330

WARNING Because the -hosts map allows NFS access to any reachable

remote system, a user may inadvertently cause an NFS mount

over X.25 or SLIP, which is unsupported, or through a slow

router or gateway. Mounts over slow links may cause excessive

retransmissions and degrade performance for all users.

When a user or process requests a directory from an NFS server, AutoFS

creates a subdirectory, named after the NFS server, under the local

mount point you conﬁgured in the AutoFS master map. (The

conventional mount point for the -hosts map is /net.) Then, AutoFS

mounts the exported directories (that are accessed with on-demand

mounting) from that server.

Directories will stay mounted until they are left idle for 10 minutes. You

can change the 10-minute default time by adding the -t

duration

option to the AUTOMOUNT_OPTIONS variable in the

/etc/rc.config.d/nfsconf ﬁle or by running the automount

command with the -t option from the command line.

The -hosts map is an indirect map. It uses the hosts database (the

/etc/hosts ﬁle, the NIS hosts map, or BIND [DNS]) to ﬁnd a host on

the network. The Name Service Switch conﬁguration determines which

name services will be searched for the host information. See the

“Conﬁguring the Name Service Switch” chapter of NFS Services

Administrator’s Guide.

For example, if the sage server exports /opt and /apps, and a user on

your NFS client types the following command:

cd /net/sage/opt/frame

the /sage subdirectory is created under /net, and /opt is mounted

under /sage using on-demand mounting.