focal (5) autofs.conf.5.gz

Provided by: autofs_5.1.6-2ubuntu0.1_amd64 bug

NAME

       autofs.conf - autofs configuration

DESCRIPTION

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

SECTION autofs CONFIGURATION OPTIONS

       Configuration settings available are:

       timeout
              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.

       master_wait
              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).

       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_verbose
              Use the verbose flag when spawning mount(8), and log some process info about the requestor and its
              parent (program default "no").

       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
              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.

       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").

       force_standard_program_map_env
              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").

       map_hash_table_size
              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.

       use_hostname_for_mounts
              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.

       disable_not_found_message
              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.

       use_ignore_mount_option
              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 omitted from mount table listings. The default is "no"
              to avoid unexpected changes in behaviour and so is an opt-in setting.

       sss_master_map_wait
              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.

       use_mount_request_log_id
              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:

       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 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 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 receives 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 will not work as
              expected.

       auth_conf_file
              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.

SECTION amd CONFIGURATION OPTIONS

       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.

       print_pid
              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.

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

       sun_map_syntax
              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.

       ldap_proto_version
              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.

       localhost_address
              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:

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

       print_version
              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.

       restart_mounts
              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).

       forced_unmounts
              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:

       search_path
              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 well.

       fully_qualified_hosts
              Not yet implemented.

       unmount_on_exit
              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.

       browsable_dirs
              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.

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

       tag
              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.

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

       cluster
              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.

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

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

       map_defaults
              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.

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

       dismount_interval
              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.

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

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

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

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

       domain_strip
              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.

       normalize_slashes
              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.

       ldap_base
              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.

       ldap_hostports
              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.

       hesiod_base
              Sets the base name used for hesiod map sources.

       linux_ufs_mount_type
              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.

EXAMPLE

         [ 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

SEE ALSO

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

AUTHOR

       This manual page was written by Ian Kent <raven@themaw.net>.

                                                   23 Jan 2014                                    AUTOFS.CONF(5)