Provided by: am-utils_6.2+rc20110530-1ubuntu1_i386 bug

NAME

       amd - automatically mount file systems

SYNOPSIS

       amd -H
       amd [ -F conf_file ]
       amd  [  -nprvHS ] [ -a mount_point ] [ -c duration ] [ -d domain ] [ -k
       kernel-arch ] [ -l logfile ] [ -o op_sys_ver ] [ -t interval.interval ]
       [  -w  interval  ]  [ -x log-option ] [ -y YP-domain ] [ -A arch ] [ -C
       cluster-name ] [ -D option ] [ -F conf_file ] [ -O op_sys_name ]  [  -T
       tag ] [ directory mapname [ -map-options ] ] ...

DESCRIPTION

       Amd  is  a daemon that automatically mounts filesystems whenever a file
       or directory within  that  filesystem  is  accessed.   Filesystems  are
       automatically unmounted when they appear to have become quiescent.

       Amd  operates  by  attaching  itself  as  an  NFS server to each of the
       specified directories.  Lookups within the  specified  directories  are
       handled  by amd, which uses the map defined by mapname to determine how
       to resolve the lookup.  Generally, this  will  be  a  host  name,  some
       filesystem information and some mount options for the given filesystem.

       In  the  first form depicted above, amd will print a short help string.
       In the second form, if no options are specified, or the -F is used, amd
       will  read  configuration  parameters  from  the  file  conf_file which
       defaults to /etc/amd.conf.  The last form is described below.

OPTIONS

       -a temporary-directory
              Specify an alternative location for the real mount points.   The
              default is /a.

       -c duration
              Specify  a  duration,  in seconds, that a looked up name remains
              cached when not in use.  The default is 5 minutes.

       -d domain
              Specify the local domain name.  If this option is not given  the
              domain name is determined from the hostname.

       -k kernel-arch
              Specifies  the  kernel architecture.  This is used solely to set
              the ${karch} selector.

       -l logfile
              Specify a logfile in which to record mount and  unmount  events.
              If  logfile  is  the string syslog then the log messages will be
              sent to the system log daemon by syslog(3).  The default  syslog
              facility  used  is LOG_DAEMON.  If you wish to change it, append
              its name to the log file name, delimited by a single colon.  For
              example,  if  logfile  is the string syslog:local7 then Amd will
              log messages via syslog(3) using the LOG_LOCAL7 facility (if  it
              exists on the system).

       -n     Normalize  hostnames.   The  name  refereed  to  by  ${rhost} is
              normalized relative to the host database before being used.  The
              effect is to translate aliases into ``official'' names.

       -o op_sys_ver
              Override the compiled-in version number of the operating system.
              Useful when the built in version is  not  desired  for  backward
              compatibility  reasons.  For example, if the build in version is
              ``2.5.1'', you can override it to ``5.5.1'', and use older  maps
              that were written with the latter in mind.

       -p     Print  PID.   Outputs  the  process-id of amd to standard output
              where it can be saved into a file.

       -r     Restart existing mounts.  Amd will scan the mount file table  to
              determine which filesystems are currently mounted.  Whenever one
              of these would have been auto-mounted, amd inherits it.

       -t timeout.retransmit
              Specify the NFS timeout interval, in tenths of a second, between
              NFS/RPC  retries  (for  UDP  only).  The default is 0.8 seconds.
              The second value alters the retransmit counter,  which  defaults
              to  11  retransmissions.   Both  of these values are used by the
              kernel to communicate with amd.  Useful defaults are supplied if
              either or both values are missing.

              Amd  relies  on  the  kernel RPC retransmit mechanism to trigger
              mount retries.   The  values  of  these  parameters  change  the
              overall  retry  interval.   Too  long  an  interval  gives  poor
              interactive response; too short  an  interval  causes  excessive
              retries.

       -v     Version.   Displays  version  and  configuration  information on
              standard error.

       -w interval
              Specify an interval, in seconds, between  attempts  to  dismount
              filesystems  that have exceeded their cached times.  The default
              is 2 minutes.

       -x options
              Specify run-time logging  options.   The  options  are  a  comma
              separated list chosen from: fatal, error, user, warn, info, map,
              stats, defaults, and all.  Note that  "fatal"  and  "error"  are
              mandatory and cannot be turned off.

       -y domain
              Specify  an  alternative  NIS domain from which to fetch the NIS
              maps.  The default is the system domain name.   This  option  is
              ignored if NIS support is not available.

       -A arch
              Specifies  the  OS architecture.  This is used solely to set the
              ${arch} selector.

       -C cluster-name
              Specify an alternative HP-UX cluster name to use.

       -D option
              Select from a variety of debug  options.   Prefixing  an  option
              with the strings no reverses the effect of that option.  Options
              are cumulative.  The most useful option is  all.   Since  -D  is
              only  used  for debugging other options are not documented here:
              the current supported set of options is listed by the -v  option
              and a fuller description is available in the program source.

       -F conf_file
              Specify  an  amd configuration file to use.  See amd.conf(5) for
              description of this file's format.  This configuration  file  is
              used  to  specify  any options in lieu of typing many of them on
              the command line.  The amd.conf  file  includes  directives  for
              every  command  line option amd has, and many more that are only
              available   via   the   configuration   file   facility.     The
              configuration  file  specified by this option is processed after
              all other options had been processed, regardless of  the  actual
              location of this option on the command line.

       -H     Print help and usage string.

       -O op_sys_name
              Override  the  compiled-in name of the operating system.  Useful
              when the built in name is not desired for backward compatibility
              reasons.   For  example, if the build in name is ``sunos5'', you
              can override it to ``sos5'',  and  use  older  maps  which  were
              written with the latter in mind.

       -S     Do not lock the running executable pages of amd into memory.  To
              improve amd's performance, systems  that  support  the  plock(3)
              call, could lock the amd process into memory.  This way there is
              less chance the operating system will schedule,  page  out,  and
              swap  the  amd  process  as  needed.   This tends improves amd's
              performance, at the cost of reserving the memory used by the amd
              process  (making  it  unavailable for other processes).  If this
              behavior is not desired, use the -S option.

       -T tag Specify a tag to use with amd.conf(5).  All map  entries  tagged
              with tag will be processed.  Map entries that are not tagged are
              always processed.  Map entries that are tagged with a tag  other
              than tag will not be processed.

FILES

       /a   directory under which filesystems are dynamically mounted

       /etc/amd.conf
            default configuration file

CAVEATS

       Some care may be required when creating a mount map.

       Symbolic  links on an NFS filesystem can be incredibly inefficient.  In
       most implementations of NFS, their interpolations are not cached by the
       kernel  and  each  time  a  symlink  is  encountered  during a lookuppn
       translation it costs an RPC call to the NFS server.   It  would  appear
       that  a  large  improvement in real-time performance could be gained by
       adding  a  cache  somewhere.   Replacing  symlinks  with   a   suitable
       incarnation  of  the auto-mounter results in a large real-time speedup,
       but also causes a large number of process context switches.

       A weird imagination is most useful to gain full advantage  of  all  the
       features.

SEE ALSO

       amq(8),  domainname(1),  hostname(1), syslog(3).  amd.conf(5), mtab(5),
       automount(8), mount(8), umount(8),

       ``am-utils'' info(1) entry.

       Linux  NFS  and  Automounter  Administration  by   Erez   Zadok,   ISBN
       0-7821-2739-8, (Sybex, 2001).

       http://www.am-utils.org

       Amd - The 4.4 BSD Automounter

AUTHORS

       Jan-Simon  Pendry <jsp@doc.ic.ac.uk>, Department of Computing, Imperial
       College, London, UK.

       Erez Zadok  <ezk@cs.sunysb.edu>,  Computer  Science  Department,  Stony
       Brook University, Stony Brook, New York, USA.

       Other  authors  and  contributors to am-utils are listed in the AUTHORS
       file distributed with am-utils.

                                3 November 1989                         AMD(8)