AUTOFS.CONF(5)                File Formats Manual               AUTOFS.CONF(5)

       autofs.conf - autofs configuration

       Configuration settings used by automount(8) may be changed in the
       configuration file /etc/autofs/autofs.conf.

       This file contains two primary sections, autofs and amd.

       Configuration entries may be present at the beginning of the
       configuration file without a section header and are implicitly included
       as part of the autofs section.

       Each section name is enclosed in square brackets with spaces between
       the brackets and the section name. The amd section may be followed by
       further sections, named by the top level mount point path, that contain
       per mount configuration settings.

       Configuration settings available are:

              Sets the default mount timeout in seconds. The internal program
              default is 10 minutes, but the default installed configuration
              overrides this and sets the timeout to 5 minutes to be
              consistent with earlier autofs releases.

              sets the default maximum time to wait for the master map to
              become available if it cannot be read at program start (program
              default 10, wait for 10 seconds then continue).

              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.

              Use the verbose flag when spawning mount(8), and log some
              process info about the requestor and its parent (program default

              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.

              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.

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

              Set the default protocol that mount.nfs(8) uses when performing
              a mount (program default 3). Autofs needs to know the default
              NFS protocol that mount.nfs(8) uses so it can do special case
              handling for its availability probe for different NFS protocols.
              Since we can't identify this default automatically we need to
              set it in the autofs configuration.

              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).

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

              override the use of a prefix with standard environment variables
              when a program map is executed. Since program maps are run as
              the privileged user setting these standard environment variables
              opens automount(8) to potential user privilege escalation when
              the program map is written in a language that can load
              components from, for example, a user home directory (program
              default "no").

              This configuration option may be used to change the number of
              hash table slots (default 1024).

              This configuration option affects the overhead of searching the
              map entry cache for map entries when there are a large number of
              entries.  It affects the number of entries that must be looked
              at to locate a map entry in the map entry cache. For example,
              the default of 1024 and a direct map with 8000 entries would
              result in each slot containing an average of 8 entries, which
              should be acceptable.

              However, if excessive CPU usage is observed during automount
              lookups increasing this option can reduce the CPU overhead
              considerably because it reduces the length of the search chains.

              Note that the number of entries in a map doesn't necessarily
              relate to the number of entries used in the map entry cache.

              There are two distinct cases where the map hash table can make a
              significant difference, direct maps and indirect maps that use
              the "browse" option.

              For indirect maps that do not use the "browse" option entries
              are added to the map entry cache at lookup so the number of
              active cache entries, in this case, is usually much less than
              the number of entries in the map. In this last case it would be
              unusual for the map entry cache to grow large enough to warrant
              increasing the default before an event that cleans stale
              entries, a map re-read for example.

              NFS mounts where the host name resolves to more than one IP
              address are probed for availability and to establish the order
              in which mounts to them should be tried. To ensure that mount
              attempts are made only to hosts that are responding and are
              tried in the order of hosts with the quickest response the IP
              address of the host needs to be used for the mount.

              If it is necessary to use the hostname given in the map entry
              for the mount regardless, then set this option to "yes".

              Be aware that if this is done there is no defense against the
              host name resolving to one that isn't responding and while the
              number of attempts at a successful mount will correspond to the
              number of addresses the host name resolves to the order will
              also not correspond to fastest responding hosts.

              The original request to add this log message needed it to be
              unconditional.  That produces, IMHO, unnecessary noise in the
              log so a configuration option has been added to provide the
              ability to turn it off. The default is "no" to maintain the
              current behaviour.

              An option to enable the use of autofs pseudo option "disable".
              This option is used as a hint to user space that the mount entry
              should be ommitted from mount table listings. The default is
              "no" to avoid unexpected changes in behaviour and so is an opt-
              in setting.

              Set the time to wait and retry if sssd returns "no such entry"
              when starting up. When sssd is starting up it can sometimes
              return "no such entry" for a short time until it has read in the
              LDAP map information. Default is 0 seconds, don't wait.

              Set whether to use a mount request log id so that log entries
              for specific mount requests can be easily identified in logs
              that have multiple concurrent requests. Default is don't use
              mount request log ids.

   LDAP Configuration
       Configuration settings available are:

              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.

              Set the network response timeout (default 8).

              A space separated 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

              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.

              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.

              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.

              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.

              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.

              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.

              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

       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 will
              not work as expected.

              This configuration option may be used to specify an alternate
              location for the ldap authentication configuration file. See
              autofs_ldap_auth.conf(5) for more information.

       A number of the amd configuration options are not used by autofs, some
       because they are not relevant within autofs, some because they are done
       differently in autofs and others that are not yet implemented.

       Since mount_type is always autofs (because there's no user space NFS
       server) the configuration entries relating to that aren't used.  Also,
       server availability is done differently within autofs so the options
       that relate to the amd server monitoring sub-system are also not used.

       These options are mount_type, auto_attrcache, portmap_program,
       nfs_vers_ping, nfs_allow_any_interface, nfs_allow_insecure_port,
       nfs_proto, nfs_retransmit_counter, nfs_retransmit_counter_udp,
       nfs_retransmit_counter_tcp, nfs_retransmit_counter_toplvl,
       nfs_retry_interval, nfs_retry_interval_udp, nfs_retry_interval_tcp,
       nfs_retry_interval_toplvl and nfs_vers.

       Other options that are not used within the autofs implementation:

       log_file, truncate_log
              sends its output to syslog so an alternate log file (or
              truncating the log) can't be used.

              There's no corresponding option for this within autofs.

       use_tcpwrappers, show_statfs_entries
              There's no user space NFS server to control access to so this
              option isn't relevant. The show_statfs_entries can't be
              implemented for the same reason.

              There's no user space NFS server and autofs avoids using file
              based mtab whenever possible.

              Sun map format is handled by autofs itself.

       plock, show_statfs_entries, preferred_amq_port
              Are not supported by autofs.

       ldap_cache_maxmem, ldap_cache_seconds
              External ldap caching is not used by autofs.

              autofs always attempts to use the highest available ldap
              protocol version.

       cache_duration, map_reload_interval, map_options
              The map   entry cache is continually updated and stale entries
              cleaned on re-load, which is done when map changes are detected
              so these configuration entries are not used by autofs. An
              exception to this is the case where the map is large. In this
              case it may be necessary to read the whole map at startup even
              if browsing is not enabled. Adding the cache:=all option to
              map_options can be used to for this.

              This is not used within autofs. This configuration option was
              only used in the amd user space server code and is not relevant
              within autofs.

       Options that are handled differently within autofs:

              To specify a pid file name a command line option must be used on

              Program version and feature information is obtained by using the
              automount command line option "-V".

       debug_options ,  log_options
              autofs has somewhat more limited logging and debug logging
              options.  When the log_options options is encountered it is
              converted to the nearest matching autofs logging option. Since
              the configuration option debug_options would be handled the same
              way it is ignored.

              This option has no sensible meaning within autofs because autofs
              always tries to re-connect to existing mounts. While this has
              its own set of problems not re-connecting to existing mounts
              always results in a non-functional automount tree if mounts were
              busy at the last shutdown (as is also the case with amd when
              using mount_type autofs).

              Detaching mounts often causes serious problems for users of
              existing mounts. It is used by autofs in some cases, either at
              the explicit request of the user (with a command line or init
              option) and in some special cases during program operation but
              is avoided whenever possible.

       A number of configuration options are not yet implemented:

              Always a little frustrating, the compiled in map location should
              be used to locate maps but isn't in some cases. This requires
              work within autofs itself and that will (obviously) include
              implementing this configuration option for the amd map parser as

              Not yet implemented.

              Since autofs always tries to re-connect to mounts left mounted
              from a previous shutdown this is a sensible option to implement
              and that will be done.

              Allow map keys to be shown in directory listings. This option
              can have values of "yes" or "no". The default is "no". A
              variation of this option, "browsable", can be used as a pseudo
              mount option in type "auto" map entries to provide browsing
              functionality in sub-mounts. The amd "browsable_dirs = full"
              option cannot be implemented within the current autofs framework
              and is not supported.

              A timeout is not currently used for program maps but this might
              be implemented in the future.

              The tag option is not implemented within autofs.

       Supported options:

       arch, karch, os, osver
              These options default to what is returned from uname(2) and can
              be overridden if required.

              This option has no default and must be set in the configuration
              if used in maps.

              If not set defaults to the host domain name. This option
              corresponds to the HP_UX cluster name (according to the amd
              source) and is probably not used in Linux but is set anyway.

       vendor This option has a default value of "unknown", it must be set in
              the configuration if used in maps.

              Is the base name of the mount tree used for external mounts that
              are sometimes needed by amd maps. Its default value is "/a".

              Specifies the autofs map source, such as file, nis, ldap etc.
              and has no default value set.

              This option is used to override /defaults entries within maps
              and can be used to provide different defaults on specific
              machines without having to modify centrally managed maps. It is
              empty by default.

              Colon separated paths to search for maps that are not specified
              as a full path.

              Is equivalent to the autofs timeout option. It is only possible
              to use this with type "auto" mounts due to the way the autofs
              kernel module performs expiry. It takes its default value from
              the autofs internal default of 600 seconds.

              If set to "yes" autofs will attempt to use bind mounts for type
              "link" entries when possible (default is "yes").

              Allows setting of a domain name other than the system default.

              Is used to override (or set) the host domain name.

              If set to "yes" then the contents of ${rhost} is translated in
              its official host name.

              If set to "yes" the domain name part of the host is stripped
              when normalizing hostnames. This can be useful when using of the
              same maps in a multiple domain environment.

              This option is set to "yes" by default and will collapse
              multiple unescaped occurrences of "/" to a single "/".

       selectors_in_defaults, selectors_on_default
              This option has a default value of "no". If set to "yes" then
              any defaults entry will be checked for selectors to determine
              the values to be used. selectors_in_defaults is the preferred
              option to use.

              iThis option has no default value. It must be set to the base dn
              that is used for queries if ldap is to be used as a map source.

              This option has no default value set. It must be set to the URI
              of the LDAP server to be used for lookups when ldap is used as a
              map source. It may contain a comma or space separated list of
              LDAP URIs.

              Sets the base name used for hesiod map sources.

              This is an additional configuration option for the autofs amd
              format parser implementation.

              There's no simple way to determine what the system default
              filesystem is and am-utils needs to be continually updated to do
              this and can easily get it wrong ayway. So allow it to be set in
              the configuration.

         [ autofs ]
         timeout = 300
         browse_mode = no

         [ amd ]
         dismount_interval = 300
         map_type = nis
         autofs_use_lofs = no

         [ /expamle/mount ]
         dismount_interval = 60
         map_type = file

       automount(8), auto.master(5), autofs_ldap_auth.conf(5).

       This manual page was written by Ian Kent <>.

                                  23 Jan 2014                   AUTOFS.CONF(5)