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fstab-sync(8) fstab-sync(8)
NAME
fstab-sync - Update the /etc/fstab file in response to HAL events
SYNOPSIS
fstab-sync [-cv?] [-a|--add UDI] [-r|--remove UDI] [-c|--clean]
[-v|--verbose] [-?|--help] [--usage]
DESCRIPTION
This program serves one major purpose: Update the file systems table
file /etc/fstab and create/remove mount points in /media in response
to HAL events. This program is usually never run directly from a
shell; instead it is invoked as a callout from the /etc/hal/device.d
directory by the HAL daemon.
Additionally, this program offers an option of removing any trace of
its previous actions from the file systems table file. Specifically
this happens when invoked by the HAL daemon for the root computer
device object which only happens when the HAL daemon is starting up.
Thus, when starting the HAL daemon, the /etc/fstab file will be com-
pletely sanitized, e.g. all entries previously added by the fstab-sync
program will be removed. When probing for hardware during the startup
of the HAL daemon, the fstab-sync program will be invoked several
times to add new entries to the /etc/fstab file.
All entries added to /etc/fstab by fstab-sync can be identified by the
use of the option managed in the options field. This option is a no-
op; it is only used to uniquely identify entries added by the fstab-
sync program.
When the /etc/fstab file is written by fstab-sync, a comment with a
link to this manual page is added to the file.
CONTROLLING WHAT ENTRIES TO ADD
The fstab-sync program relies on properties on the relevant HAL device
objects in order to determine if and how an entry to the /etc/fstab
file should be added. Specifically, entries are added for hal device
objects of respectively capability storage and volume only if appro-
priate storage.policy and volume.policy properties are set. Also, the
storage.policy.default properties on the root computer device object
are taken into account. See the HAL specification on http://freedesk-
top.org/Software/hal for more information.
By default, the /usr/share/hal/fdi/90defaultpolicy/storage-policy.fdi
file specifies the policy - this file should never be edited by the
system administrator as it might get updated by the OS vendor for
security updates. Instead, system- or site-specific rules can be put
in the /usr/share/hal/fdi/95userpolicy directory.
Device information files are processed for every hal device object in
the /usr/share/hal/fdi/ directory in alphabetical order including
directories. Hence, files in the 90defaultpolicy directory are pro-
cessed before files 95userpolicy directory, 95userpolicy/a.fdi is pro-
cessed before 95userpolicy/b.fdi and so on. In addition, directives in
specific files are processed in a top-down fashion.
A number of sample policy files for various uses should be available
in the /usr/share/doc/hal-0.4.2/conf directory. For example, the pol-
icy file storage-non-fixed.fdi ensures that only fixed optical and
floppy drives gets tagged as mountable which ensures that e.g. hard
disk partitions on a fixed disk won't get added to the /etc/fstab
file. Similarly the storage-skip-all.fdi file will ensure no entries
are ever added.
DISABLING FSTAB-SYNC
Automatic updates of the /etc/fstab file by the fstab-sync program
from the HAL daemon can be disabled by changing the 50-fstab-sync.hal
symlink in /etc/hal/device.d directory to point to /bin/false
OPTIONS
The following options are supported:
--add=UDI
Add an entry to the /etc/fstab file by giving a HAL Unique
Device Identifier
--remove=UDI
Remove an entry from fstab by giving a HAL Unique Device Iden-
tifier
--clean
Clean all entries generated by fstab-sync from the /etc/fstab
file
--verbose
Report detailed information about operation progress
--usage
Display brief usage message
--help Show options
LOCKING
The fstab-sync program uses flock(2) for locking the /etc/fstab file
when adding or removing entries. This happens when the HAL daemon
starts up, when there's a media change event or when a storage device
is hotplugged.
SEE ALSO
fstab(5), http://freedesktop.org/Software/hal
BUGS
One known bug is that the HAL daemon has to be running when cleaning
the /etc/fstab file. Please send bug reports to the appropriate dis-
tribution bug tracker or the HAL mailing list - see http://freedesk-
top.org/Software/HalTraces for more information.
fstab-sync(8)
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