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NAME

       auto.master - Master Map for automounter

DESCRIPTION

       The  auto.master  map  is  consulted  to set up automount managed mount
       points when the autofs(8) script is invoked or the automount(8) program
       is  run.  Each line describes a mount point and refers to an autofs map
       describing file systems to be mounted under the mount point.

       The default location of the  master  map  is  /etc/auto.master  but  an
       alternate  name  may  be  given  on  the  command line when running the
       automounter and the default master  map  may  changed  by  setting  the
       MASTER_MAP_NAME  configuration variable in /etc/default/autofs.  If the
       master map name has  no  path  then  the  system  Name  Service  Switch
       configuration  will  be  consulted  and each of the sources searched in
       line with the rules given in the Name Service Switch configuration.

       Access to mounts in maps is governed by a key.

       For direct maps the mount point is always specified as:

       /-

       and the key used within the direct map is the full path  to  the  mount
       point.

       For indirect maps access is by using the path scheme:

       /mount-point/key

       where  mount-point  is one of the entries listed in the master map. The
       key is a single directory component and is matched against  entries  in
       the map given in the entry (See autofs(5)).

       Additionally,  a  map  may  be  included  from its source as if it were
       itself present in the master map by  including  a  line  of  the  form:
       + [maptype,format:]map[options]  and  automount(8) will process the map
       according to the specification described below for map entries.

FORMAT

       Master map entries have three fields separated by an  arbitrary  number
       of spaces or tabs. Lines beginning with # are comments. The first field
       is the mount point described above and the second field is the name  of
       the map to be consulted for the mount point followed by the third field
       which contains options to be applied to all entries in the map.

       The format of a master map entry is:

       mount-point [map-type[,format]:]map [options]

       mount-point
              Base location for the autofs  filesystem  to  be  mounted.   For
              indirect  maps this directory will be created (as with mkdir -p)
              and is removed when the autofs filesystem is umounted.

       map-type
              Type of map used for this mount point.  The following are  valid
              map types:

              file   The map is a regular text file.

              program
                     The  map  is an executable program, which is passed a key
                     on the command line  and  returns  an  entry  (everything
                     besides the key) on stdout if successful.

              yp     The map is a NIS (YP) database.

              nisplus
                     The map is a NIS+ database.

              hesiod The  map  is  a  hesiod database whose filsys entries are
                     used for maps.

              ldap or ldaps
                     The map is stored in an LDAP directory. If ldaps is  used
                     the  appropriate  certificate  must  be configured in the
                     LDAP client.

              multi  This map type allows the specification of  multiple  maps
                     separated  by  "--".  These maps are searched in order to
                     resolve key lookups.

       format Format of the map data; currently the  only  formats  recognized
              are  sun,  which  is a subset of the Sun automounter map format,
              and hesiod, for hesiod filesys entries.  If the format  is  left
              unspecified, it defaults to sun for all map types except hesiod.

       map    Name of the map to use.  This is an absolute UNIX  pathname  for
              maps of types file or program, and the name of a database in the
              case for maps of type yp, nisplus, or hesiod or  the  dn  of  an
              LDAP entry for maps of type ldap.

       options
              Any  remaining command line arguments without leading dashes (-)
              are taken as options (-o)  to  mount.   Arguments  with  leading
              dashes are considered options for the maps.

              The sun format supports the following options:

              -Dvariable=value
                     Replace variable with value in map substitutions.

              -strict
                     Treat errors when mounting file systems as fatal. This is
                     important when multiple file systems  should  be  mounted
                     (‘multimounts’).  If this option is given, no file system
                     is mounted at all if at least one file  system  can’t  be
                     mounted.

              nosymlink
                     This  is an autofs specific option that is a pseudo mount
                     option  and  so  is  given  without   a   leading   dash.
                     Historically  this  option was used to prevent symlinking
                     of local NFS mounts. Nowadays it can be used  to  prevent
                     bind  mounting  of  local NFS filesystems as well. If you
                     need to prevent bind mounting for only specific entrys in
                     a  map  then this can be done by adding the "port=" mount
                     option to the given entries.

              -r, --random-multimount-selection
                     Enables the use of ramdom selection when choosing a  host
                     from a list of replicated servers. This option is applied
                     to this mount only, overriding the  global  setting  that
                     may be specified on the command line.

              -n, --negative-timeout <seconds>
                     Set  the  timeout  for  caching  failed key lookups. This
                     option can be used to override the global  default  given
                     either on the command line or in the configuration.

GENERAL SYSTEM DEFAULTS CONFIGURATION

       The  default  value  of  several general settings may be changed in the
       configuration file /etc/default/autofs.  They are:

       TIMEOUT
              sets the default mount timeout (program default 600).

       NEGATIVE_TIMEOUT
              Set the default timeout for caching failed key lookups  (program
              default  60).  If the equivalent command line option is given it
              will override this setting.

       MOUNT_WAIT
              Set the default time to wait  for  a  response  from  a  spawned
              mount(8) before sending it a SIGTERM. Note that we still need to
              wait for the RPC layer to timeout before the  sub-process  exits
              so this isn’t ideal but it is the best we can do. The default is
              to wait until mount(8) returns without intervention.

       UMOUNT_WAIT
              Set the default time to wait  for  a  response  from  a  spawned
              umount(8)  before  sending it a SIGTERM. Note that we still need
              to wait for the RPC layer  to  timeout  before  the  sub-process
              exits so this isn’t ideal but it is the best we can do.

       BROWSE_MODE
              Maps are browsable by default (program default "yes").

       MOUNT_NFS_DEFAULT_PROTOCOL
              Specify  the  default  protocol  used  by  mount.nfs(8) (program
              default 3). Since we can’t identify this  default  automatically
              we  need to set it in the autofs configuration. This option will
              only  make  a  difference  for   replicated   map   entries   as
              availability probing isn’t used for single host map entries.

       APPEND_OPTIONS
              Determine  whether  global options, given on the command line or
              per mount in the master map, are appended to map  entry  options
              or  if the map entry options replace the global options (program
              default "yes", append options).

       LOGGING
              set default log level  "none",  "verbose"  or  "debug"  (program
              default "none").

BUILTIN MAP -hosts

       If  "-hosts"  is  given as the map then accessing a key under the mount
       point which corresponds to a hostname will allow access to the  exports
       of that host.

       For  example,  with an entry in the master map of /net -hosts accessing
       /net/myserver will mount exports from  myserver  on  directories  below
       /net/myserver.

       NOTE:   mounts  done  from  a  hosts  map  will  be  mounted  with  the
       "nosuid,nodev,intr" options unless overridden by  explicily  specifying
       the "suid", "dev" or "nointr" options in the master map entry.

LDAP MAPS

       If  the  map  type  ldap  is  specified  the  mapname  is  of  the form
       [//servername/]dn, where the optional servername is  the  name  of  the
       LDAP  server to query, and dn is the Distinguished Name of a subtree to
       search for map entries.  The old style ldap:servername:mapname is  also
       understood.  Alternatively,  the  type  can  be  obtained from the Name
       Service Switch configuration, in which case the map name alone must  be
       given.

       If  no schema is set in the autofs configuration then autofs will check
       each of the commonly used schema for a valid entry and if one is  found
       it will used for subsequent lookups.

       There are three common schemas in use:

       nisMap Entries  in  the  nisMap  schema  are  nisObject  objects in the
              specified subtree, where  the  cn  attribute  is  the  key  (the
              wildcard key is "/"), and the nisMapEntry attribute contains the
              information used by the automounter.

       automountMap
              The automountMap schema has two variations that  differ  in  the
              attribute  used  for  the  map  key. Entries in the automountMap
              schema are automount objects in the specified subtree, where the
              cn  or  automountKey attribute (depending on local usage) is the
              key (the wildcard key  is  "/"),  and  the  automountInformation
              attribute contains the information used by the automounter. Note
              that the cn attribute is case insensitive.

       The object classes and attributes used for accessing automount maps  in
       LDAP  can  be  changed  by  setting entries in the autofs configuration
       located in /etc/default/autofs.

       NOTE:  If a schema is given in the configuration then  all  the  schema
              configuration   values   must   be   set,   any  partial  schema
              specification will be ignored.

       The configuration settings available are:

       LDAP_TIMEOUT
              Set the network response timeout (default 8).  Set timeout value
              for  the synchronous API  calls. The default is the LDAP library
              default of an infinite timeout.

       LDAP_NETWORK_TIMEOUT
              Set the network response timeout (default 8).

       LDAP_URI
              A  space  seperated  list   of   server   uris   of   the   form
              <proto>://<server>[/]  where  <proto>  can be ldap or ldaps. The
              option can be given multiple times.  Map entries that include  a
              server  name  override  this  option  and  it  is then not used.
              Default is an empty list in which case either the  server  given
              in  a map entry or the LDAP configured default is used. This uri
              list is read at startup and whenever the daemon receives  a  HUP
              signal.

       This configuration option can also be used to request autofs lookup SRV
       RRs for a domain of the form  <proto>:///[<domain  dn>].  Note  that  a
       trailing  "/"  is not allowed when using this form. If the domain dn is
       not specified the dns domain name (if any) is  used  to  construct  the
       domain  dn  for the SRV RR lookup. The server list returned from an SRV
       RR lookup is refreshed according to the minimum ttl found in the SRV RR
       records or after one hour, whichever is less.

       SEARCH_BASE
              The  base  dn to use when searching for amap base dn. This entry
              may be given multiple times and each will be checked for  a  map
              base dn in the order they occur in the configuration. The search
              base list is read at startup and whenever the daemon recieves  a
              HUP signal.

       MAP_OBJECT_CLASS
              The  map  object class. In the nisMap schema this corresponds to
              the class nisMap and in the automountMap schema  it  corresponds
              to the class automountMap.

       ENTRY_OBJECT_CLASS
              The   map   entry  object  class.  In  the  nisMap  schema  this
              corresponds to the  class  nisObject  and  in  the  automountMap
              schema it corresponds to the class automount.

       MAP_ATTRIBUTE
              The attribute used to identify the name of the map to which this
              entry belongs.  In the nisMap schema  this  corresponds  to  the
              attribute   nisMapName   and   in  the  automountMap  schema  it
              corresponds to the attribute ou or automountMapName.

       ENTRY_ATTRIBUTE
              The attribute used to identify a map key. In the  nisMap  schema
              this  corresponds  to  the  attribute cn and in the automountMap
              schema it corresponds to the attribute automountKey.

       VALUE_ATTRIBUTE
              The attribute used to identify the value of the  map  entry.  In
              the  nisMap schema this corresponds to the attribute nisMapEntry
              and in the automountMap schema it corresponds to  the  attribute
              automountInformation.

       NOTE:  It  is  essential  that  entries  use  class  and attribute in a
              consistent manner for correct operation of autofs.  For  example
              mixing  cn  and  automountKey attributes in automount schema map
              entries won’t work as expected.

LDAP AUTHENTICATION, ENCRYPTED AND CERTIFIED CONNECTIONS

       LDAP authenticated binds, TLS encrypted connections  and  certification
       may  be used by setting appropriate values in the autofs authentication
       configuration file and configuring the  LDAP  client  with  appropriate
       settings.      The     default     location    of    this    file    is
       /etc/autofs_ldap_auth.conf.  If this file exists it  will  be  used  to
       establish whether TLS or authentication should be used.

       An example of this file is:

         <?xml version="1.0" ?>
         <autofs_ldap_sasl_conf
                 usetls="yes"
                 tlsrequired="no"
                 authrequired="no"
                 authtype="DIGEST-MD5"
                 user="xyz"
                 secret="abc"
         />

       If  TLS  encryption  is  to  be  used  the  location of the Certificate
       Authority certificate must be set within the LDAP client  configuration
       in  order  to  validate  the  server  certificate.  If,  in addition, a
       certified connection is to be used  then  the  client  certificate  and
       private  key  file  locations  must  also be configured within the LDAP
       client.

       In OpenLDAP these may be configured in the ldap.conf  file  or  in  the
       per-user  configuration.  For  example  it  may  be sensible to use the
       system wide configuration for the location of the Certificate Authority
       certificate  and set the location of the client certificate and private
       key in the per-user configuration. The location of these files and  the
       configuration   entry   requirements   is   system   dependent  so  the
       documentation for your installation will need to be  consulted  to  get
       further information.

       See autofs_ldap_auth.conf(5) for more information.

EXAMPLE

         /-        auto.data
         /home     /etc/auto.home
         /mnt      yp:mnt.map

       This  will  generate  two  mountpoints  for  /home and /mnt and install
       direct mount triggers for each entry in the direct mount map auto.data.
       All  accesses  to  /home  will  lead  to the consultation of the map in
       /etc/auto.home and all accesses  to  /mnt  will  consult  the  NIS  map
       mnt.map.   All  accesses  to  paths  in  the map auto.data will trigger
       mounts when they are accessed and the Name Service Switch configuration
       will be used to locate the source of the map auto.data.

SEE ALSO

       automount(8), autofs(5), autofs(8).  autofs_ldap_auth.conf(5)

AUTHOR

       This  manual  page was written by Christoph Lameter <chris@waterf.org>,
       for the Dean GNU/Linux system.  Edited by <hpa@transmeta.com>  and  Ian
       Kent <raven@themaw.net> .

                                  11 Apr 2006