source: trunk/athena/bin/attach/attach.conf.5 @ 5481

.TH ATTACH.CONF 5  "July 4, 1989"
.SH NAME
attach.conf \- attach configuration file
.SH DESCRIPTION
The behavior of 
.IR Attach , detach , 
and
.I nfsid
are controlled by attach.conf.  These programs read /etc/athena/attach.conf
when they start up, so the system administrator can customize their
behavior without needing to recompile the programs.

The format of attach.conf is line oriented, with one configuration
option per line.  Blank lines and lines which begin with a pound sign
(#) are ignored as comments.  The configuration keyword is the first
whitespace-delimited string on the line, with its arguments following
it, also delimited by whitespace.

There are several different types of keywords, which determine what
type of argument or arguments they require.
.IP boolean
Keywords of type boolean are typically options which can be
enabled or disabled, as specified by their arguments.  Legal arguments
are 
.I on 
or 
.IR off .
.IP string
Keywords of type string are typically filenames.  Any argument
is legal; the configuration option is assigned the first
argument following the keyword.
.IP user-list
Keywords of type user-list take one or more arguments, which may
either be a number representing a user-id or a username.
.IP regexp-argument
Keywords of type regexp-argument take the first argument as a regular
expression.  The remainder of the line is kept as a string which
applies if the regular expression matches the filesystem being
attached or detached.  
.IP regexp-list
Keywords of type regexp-list take oneor more arguments, which are
regular expressions.
.PP
The following keywords are supported in attach.conf:
.IP "verbose (type boolean) (default: on)"
If this option is on, then messages indicating success or failure are
printed as each filesystem is attached or detached.  If this option is
off, only error messages are printed.
.IP "debug (type boolean) (default: off)"
If this option is on, then various debuging messages are printed as
the attach or detach operation proceeds.  This is normally only of
interest to attach developers.
.IP "ownercheck (type boolean) (default: off)"
If this option is on, then only the user which attached a filesystem
may detach it.  
.I Trusted users
(as specified by the 
.B trusted 
keyword) may use the -override (-O) flag to forcibly detach a
filesystem attached by another user.
.IP "keep-mount (type boolean) (default: off)"
If this option is on, then when a user attaches a filesystem
which is already mounted but not in attachtab a flag is set so that
when that filesystem is detached, its entry is removed from attachtab
without unmounting it.  This is useful to prevent users from being
able to forcibly unmount partitions by attaching them and then
detaching them.
.IP "nfs-root-hack (type boolean) (default: on)"
This option affects the construction of the default mount point for
explicit NFS attaches.  The default mount point is constructed by
appending the value of 
.I nfs-mount-dir 
followed by the hostname of the NFS server, followed by the remotely
mounted directory.  If 
.I nfs-root-hack
is on, then if the remotely mounted directory is the root (/), it is
replaced by ``/root'' for the purposes of contructing the default
mount point.
.IP "nfs-mount-dir (type string) (default: /)"
This option affects the construction of the default mount point for
explicit NFS attaches.  See the description for
.I nfs-root-hack
above.
.IP "attachtab (type string) (default: /usr/tmp/attachtab)"
This option specifies the location of the
.I attachtab(5)
file.  It is generally located in /usr/tmp, /etc, or /site/etc.
.IP "mtab (type string) (default: /etc/mtab)"
This option specifies the location of the 
.I mtab(5)
file.  Since other programs, such as mount(8) and umount(8) expect
mtab to be in /etc, it is probably unwise to change the location of
this file.
.IP "aklog (type string)"
(default: /afs/athena/mit/andrew/@sys/aklog)

This keyword specifies the location of the
.I aklog
- program.  It is used to authenticate the user to the AFS system.
.IP "fsck (type string) (default: /etc/fsck)"
This option specifies the location of 
.IR fsck(8) ,
which is used to check the integrity of a Unix filesystem.  It is used
when UFS or RVD filesystems are attached.
.IP "trusted (type user-list) (default: root)"
This option allows the system administrator to specify a list of
trusted users who are allowed to use certain restricted options found
in 
.I attach(1)
and 
.IR detach(1) .
This includes the ability to detach a filesystem owned by another user
(if ownercheck is enabled) and the ability to force a filesystem to be
mounted without the nosuid mount option.
.IP "nosetuid or nosuid (type regexp-list)"
Filesystems which match the regular expresions listed as arguments are
mounted with the nosuid flag.  This instructs the operating system to
disregard set-uid flags found on files in the mounted filesystem.
(See mount(8) for more information.) 
.IP "setuid or suid (type regexp-list)"
Filesystems which match the regular expresions listed as arguments are
mounted without the nosuid flag.
.IP "allow (type regexp-list)"
Filesystems which match the regular expresions listed as arguments may
be mounted with attach.
.IP "noallow (type regexp-list)"
Filesystems which match the regular expresions listed as arguments may
not be mounted with attach.  This prohibition can be bypassed with the
-override (-O) flag, if the user is one of the ``trusted users.''
.IP "mountpoint (type regexp-list)"
Mountpoint which match one of the regular expressions listed as
arguments are allowed.
.IP "nomountpoint (type regexp-list)"
Mountpoint which match one of the regular expressions listed as
arguments are not allowed.   This prohibition can be bypassed with the
-override (-O) flag, if the user is one of the ``trusted users.''
.IP "filesystem (type string-argument)"
This keyword allows the system administrator to give a filesystem
definition for a filesystem.  Definitions in attach.conf take
precedence over Hesiod(3) definitions..
.IP "options (type regexp-argument)"
Filesystems which match the regular expresions listed as arguments are
mounted with the specified argument as a mount option.  This is
particularly useful in forcing the NFS packet size to something which
can be handled by local gateways.  This can be done including the
following line in attach.conf:
.IP
options {nfs}:.*        rsize=1024,wsize=1024
.PP
.SH "FILESYSTEM DEFINITIONS"
Filesystem definitions are used by attach to determine how a named
filesystem should be attached.  These definitions can be found either
in attach.conf or by performing Hesiod(3) lookup.  In general, the
definition consists of a filesystem type (NFS, RVD, UFS, etc.)
followed by information specific to that fileststem type.  Here are
some typical filesystem definitions, as would be found in
attach.conf (in Hesiod, the first two fields would be absent and the
definition would be keyed to a filesystem name):

.nf
filesystem thor:site    UFS /dev/ra0g w /site
filesystem priam:slush  NFS /slush priam w /priam/slush
filesystem tytso-afs    AFS /afs/athena/mit/tytso w /mit/tytso-afs
filesystem bldge40test-vsusr-63A        AFS /afs/testers/@sys/urvd r /urvd
filesystem bldgw20-vsusr-62A filsys     RVD vsusr slartibartfast r /urvd
filesystem games        ERR Sorry, the games filesystem is not available
.fi
.PP
The following are the supported filesystem types and the format a
filesystem definition for that type:
.IP NFS
.IP RVD
.IP UFS
.IP AFS
.IP ERR
.SH "EXTENSIONS TO REGEULAR EXPRESIONS"
Regular expressions in an attach.conf file can be prefixed by a 
.IR type-delimiter ,
an optional string delimited by curly braces and followed a colon.  If
this string is present, it consists of a list of filesystem types
separated by commas.  The regular expression is matched against the
filesystem only if the filesystem type matches one of the filesystem
types listed in the 
.IR type-delimiter .
The 
.I type-delimiter
may be prefixed by a caret (^), which reverses the
.I type-delimiter
check.  That is, the regular expression is considered only if the
filesystem type is 
.I not
one listed in the
.IR type-delimiter .
The 
.I type-delimiter
may be further optionally prefixed with either a plus (+) or minus (-) sign.
If present, the plus sign indicates that the regular expression should
be considered only if the filesystem was explicitly definied on the
command line.  Likewise, the minus sign indicates that the regular
expression should be considered only if the filesystem was not
explicitly definied.
.SH BUGS

.SH FILES
/etc/athena/attach.conf
.SH SEE ALSO
attach(1), attachtab(5)