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autofs(5) can mount and unmount NFS file systems automatically (on-demand mounting), therefore saving system resources. It can be used to mount other file systems including AFS, SMBFS, CIFS, and local file systems.

autofs is needed in FreeBSD to for instance automatically mount nested shares that are accessed via NFS.

To use autofs in FreeBSD first the following line has to be added to /etc/rc.conf:

autofs_enable="YES"