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(am-utils.info)Network Host Filesystem

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Network Host Filesystem (`host')
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   The "host" (`type:=host') filesystem allows access to the entire
export tree of an NFS server.  The implementation is layered above the
`nfs' implementation so keep-alives work in the same way.  The only
option which needs to be specified is `rhost' which is the name of the
fileserver to mount.

   The `host' filesystem type works by querying the mount daemon on the
given fileserver to obtain its export list.  Amd then obtains
filehandles for each of the exported filesystems.  Any errors at this
stage cause that particular filesystem to be ignored.  Finally each
filesystem is mounted.  Again, errors are logged but ignored.  One
common reason for mounts to fail is that the mount point does not exist.
Although Amd attempts to automatically create the mount point, it may
be on a remote filesystem to which Amd does not have write permission.

   When an attempt to unmount a `host' filesystem mount fails, Amd
remounts any filesystems which had successfully been unmounted.  To do
this Amd queries the mount daemon again and obtains a fresh copy of the
export list.  Amd then tries to mount any exported filesystems which
are not currently mounted.

   Sun's automounter provides a special `-hosts' map.  To achieve the
same effect with Amd requires two steps.  First a mount map must be
created as follows:

     *       type:=host;rhost:=${key};fs:=${autodir}/${rhost}/root

and then start Amd with the following command

     amd /net net.map

where `net.map' is the name of map described above.  Note that the
value of `${fs}' is overridden in the map.  This is done to avoid a
clash between the mount tree and any other filesystem already mounted
from the same fileserver.

   If different mount options are needed for different hosts then
additional entries can be added to the map, for example

     host2       opts:=ro,nosuid,soft

would soft mount `host2' read-only.