man/autofs.conf.5.in

.\" t
.TH AUTOFS.CONF "23 Jan 2014"
.SH NAME
autofs.conf \- autofs configuration
.SH "DESCRIPTION"
.P
Configuration settings used by
.BR automount (8)
may be changed in the configuration file \fB@@autofsmapdir@@/autofs.conf\fP.
.P
This file contains two primary sections, \fBautofs\fP and \fBamd\fP.
.P
Configuration entries may be present at the beginning of the
configuration file without a section header and are implicitly
included as part of the \fBautofs\fP section.
.P
Each section name is enclosed in square brackets with
spaces between the brackets and the section name. The \fBamd\fP
section may be followed by further sections, named by the
top level mount point path, that contain per mount
configuration settings.
.SH "SECTION autofs CONFIGURATION OPTIONS"
.P
Configuration settings available are:
.TP
.B timeout
.br
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.
.TP
.B 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).
.TP
.B negative_timeout
.br
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.
.TP
.B mount_wait
.br
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.
.TP
.B umount_wait
.br
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.
.TP
.B browse_mode
.br
Maps are browsable by default (program default "yes").
.TP
.B mount_nfs_default_protocol
.br
Specify the default protocol used by
.BR mount.nfs (8)
(program default 3). Since we can't identify this default automatically
we need to set it in the autofs configuration.
.TP
.B append_options
.br
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).
.TP
.B logging
.br
set default log level "none", "verbose" or "debug" (program default "none").
.TP
.B force_standard_program_map_env
.br
override the use of a prefix with standard environment variables when a
program map is executed. Since program maps are run as the privileded
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").
.TP
.B map_hash_table_size
.br
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 becuase
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 three distinct cases, direct maps and indirect maps that
use the "browse" option must be read in their entirity at program
start so, in these two cases the map size does retate directly to
the map entry cache size.

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.
.TP
.B use_hostname_for_mounts
.br
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.
.TP
.B disable_not_found_message
.br
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.
.TP
.B sss_master_map_wait
.br
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.
.SS LDAP Configuration
.P
Configuration settings available are:
.TP
.B ldap_timeout
.br
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.
.TP
.B ldap_network_timeout
.br
Set the network response timeout (default 8).
.TP
.B ldap_uri
.br
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.
.TP
.B search_base
.br
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.
.TP
.B map_object_class
.br
The map object class. In the \fBnisMap\fP schema this corresponds to the class
\fBnisMap\fP and in the \fBautomountMap\fP schema it corresponds to the class
\fBautomountMap\fP.
.TP
.B entry_object_class
.br
The map entry object class. In the \fBnisMap\fP schema this corresponds
to the class \fBnisObject\fP and in the \fBautomountMap\fP schema it
corresponds to the class \fBautomount\fP.
.TP
.B map_attribute
.br
The attribute used to identify the name of the map to which this
entry belongs.  In the \fBnisMap\fP schema this corresponds to the attribute
\fBnisMapName\fP and in the \fBautomountMap\fP schema it corresponds to the
attribute \fBou\fP or \fBautomountMapName\fP.
.TP
.B entry_attribute
.br
The attribute used to identify a map key. In the \fBnisMap\fP schema this
corresponds to the attribute \fBcn\fP and in the \fBautomountMap\fP schema
it corresponds to the attribute \fBautomountKey\fP.
.TP
.B value_attribute
.br
The attribute used to identify the value of the map entry. In the \fBnisMap\fP
schema this corresponds to the attribute \fBnisMapEntry\fP and in the \fBautomountMap\fP
schema it corresponds to the attribute
.BR automountInformation .
.TP
.B NOTE:
It is essential that entries use class and attribute in a consistent
manner for correct operation of autofs. For example mixing \fBcn\fP
and \fBautomountKey\fP attributes in \fBautomount\fP schema will
not work as expected.
.TP
.B auth_conf_file
This configuration option may be used to specify an alternate location
for the ldap authentication configuration file. See
.BR autofs_ldap_auth.conf (5)
for more information.
.SH "SECTION amd CONFIGURATION OPTIONS"
.P
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 \fBmount_type\fP 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 \fBmount_type\fP, \fBauto_attrcache\fP, \fBportmap_program\fP,
\fBnfs_vers_ping\fP, \fBnfs_allow_any_interface\fP, \fBnfs_allow_insecure_port\fP,
\fBnfs_proto\fP, \fBnfs_retransmit_counter\fP, \fBnfs_retransmit_counter_udp\fP,
\fBnfs_retransmit_counter_tcp\fP, \fBnfs_retransmit_counter_toplvl\fP,
\fBnfs_retry_interval\fP, \fBnfs_retry_interval_udp\fP, \fBnfs_retry_interval_tcp\fP,
\fBnfs_retry_interval_toplvl\fP and \fBnfs_vers\fP.

Other options that are not used within the autofs implementation:
.TP
.BR log_file ", " truncate_log
.br autofs used either stderr when running in the foreground or
sends its output to syslog so an alternate log file (or truncating
the log) can't be used.
.TP
.B print_pid
.br
There's no corresponding option for this within autofs.
.TP
.BR use_tcpwrappers ", " show_statfs_entries
.br
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.
.TP
.B debug_mtab_file
.br
There's no user space NFS server and autofs avoids using file
based mtab whenever possible.
.TP
.B sun_map_syntax
.br
Sun map format is handled by autofs itself.
.TP
.BR plock ", " show_statfs_entries ", " preferred_amq_port
.br
Are not supported by autofs.
.TP
.BR ldap_cache_maxmem ", " ldap_cache_seconds
.br
External ldap caching is not used by autofs.
.TP
.B ldap_proto_version
.br
autofs always attempts to use the highest available ldap
protocol version.
.TP
.BR cache_duration ", " map_reload_interval ", " map_options
.br
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 is not enabled. Adding the cache:=all option to
map_options can be used to for this.
.TP
.B 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.
.P
Options that are handled differently within autofs:
.TP
.B pid_file
.br
To specify a pid file name a command line option must be used on startup.
.TP
.B print_version
.br
Program version and feature information is obtained by using the
automount command line option "-V".
.TP
.B debug_options ", " log_options
.br
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.
.TP
.B restart_mounts
.br
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).
.TP
.B forced_unmounts
.br
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.
.P
A number of configuration options are not yet implemented:
.TP
.B search_path
.br
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.
.TP
.B fully_qualified_hosts
Not yet implemented.
.TP
.B unmount_on_exit
.br
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.
.TP
.B browsable_dirs
.br
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 provide browsing funtionality
in sub-mounts. The amd "browsable_dirs = full" option cannot be
implemented within the current autofs framework and is not supported.
.TP
.B exec_map_timeout
.br
A timeout is not currently used for for program maps, might be
implemented.
.TP
.B tag
.br
The tag option is not implemented within autofs.
.P
Supported options:
.TP
.BR arch ", " karch ", " os ", " osver
.br
These options default to what is returned from uname(2) and can
be overridden if required.
.TP
.B full_os
This option has no default and must be set in the configuration
if used in maps.
.TP
.B cluster
.br
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.
.TP
.B vendor
This option has a default value of "unknown", it must be set in the
configuration if used in maps.
.TP
.B auto_dir
.br
Is the base name of the mount tree used for external mounts that
are sometimes needed by amd maps. Its default value is "/a".
.TP
.B map_type
.br
Specifies the autofs map source, such as file, nis, ldap etc. and
has no default value set.
.TP
.B map_defaults
.br
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.
.TP
.B search_path
.br
Colon separated paths to search for maps that are not specified
as a full path.
.TP
.B dismount_interval
.br
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 defaulti of 600 seconds.
.TP
.B autofs_use_lofs
.br
If set to "yes" autofs will attempt to use bind mounts for type
"auto" when possible.
.TP
.B nis_domain
.br
Allows setting of a domain name other than the system default.
.TP
.B local_domain
.br
Is used to override (or set) the host domain name.
.TP
.B normalize_hostnames
.br
If set to "yes" then the contents of ${rhost} is translated in
its official host name.
.TP
.B domain_strip
.br
If set to "yes" the domain name part of the host is strippped
when normalizing hostnames. This can be useful when using of
the same maps in a multiple domain environment.
.TP
.B normalize_slashes
.br
This option is set to "yes" by default and will collapse
multiple unescaped occurrences of "/" to a single "/".
.TP
.BR selectors_in_defaults ", " selectors_on_default
.br
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.
.TP
.B ldap_base
.br
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.
.TP
.B ldap_hostports
.br
This option has no default value set. It must be set to the URI
of the LDAP server to be used for lookups wheni ldap is used a
map source. It may contain a comma or space separated list of
LDAP URIs.
.TP
.B hesiod_base
.br
Sets the base name used for hesiod map sources.
.TP
.B linux_ufs_mount_type
.br
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.
.SH EXAMPLE
.sp
.RS +.2i
.ta 1.0i
.nf
[ 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
.fi
.RE
.SH "SEE ALSO"
.BR automount (8),
.BR auto.master (5),
.BR autofs_ldap_auth.conf (5)
.SH AUTHOR
This manual page was written by Ian Kent <raven@themaw.net>.