=head1 NAME

vos_dump - Converts a volume into ASCII format and writes it to a file

=head1 SYNOPSIS

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<div class="synopsis">

B<vos dump> S<<< B<-id> <I<volume name or ID>> >>> S<<< [B<-time> <I<dump from time>>] >>>
    S<<< [B<-file> <I<dump file>>] >>> S<<< [B<-server> <I<server>>] >>>
    S<<< [B<-partition> <I<partition>>] >>> [B<-clone>] [B<-omitdirs>]
    S<<< [B<-cell> <I<cell name>>] >>> [B<-noauth>] [B<-localauth>]
    [B<-verbose>] [B<-help>]

B<vos du> S<<< B<-i> <I<volume name or ID>> >>> S<<< [B<-t> <I<dump from time>>] >>>
    S<<< [B<-f> <I<dump file>>] >>> S<<< [B<-s> <I<server>>] >>> S<<< [B<-p> <I<partition>>] >>>
    [B<-cl>] [B<-o>] S<<< [B<-ce> <I<cell name>>] >>> [B<-n>] [B<-l>]
    [B<-v>] [B<-h>]

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</div>

=head1 DESCRIPTION

The B<vos dump> command converts the contents of the indicated volume,
which can be read/write, read-only or backup, into ASCII format. The
Volume Server writes the converted contents to the file named by the
B<-file> argument, or to the standard output stream. In the latter case,
the output can be directed to a named pipe, which enables interoperation
with third-party backup utilities.

To dump the complete contents of a volume (create a I<full dump>), omit
the B<-time> argument or specify the value C<0> (zero) for it. To create
an I<incremental dump>, which includes only the files and directories in
the volume that have modification timestamps later than a certain time,
specify a date and time as the value for the B<-time> argument.

By default, the vos command interpreter consults the Volume Location
Database (VLDB) to learn the volume's location, so the B<-server> and
B<-partition> arguments are not required. If the B<-id> argument
identifies a read-only volume that resides at multiple sites, the command
dumps the version from just one of them (normally, the one listed first in
the volume's VLDB entry as reported by the B<vos examine> or B<vos
listvldb> command). To dump the read-only volume from a particular site,
use the B<-server> and B<-partition> arguments to specify the site. To
bypass the VLDB lookup entirely, provide a volume ID number (rather than a
volume name) as the value for the B<-id> argument, together with the
B<-server> and B<-partition> arguments. This makes it possible to dump a
volume for which there is no VLDB entry.

During the dump operation, the volume is inaccessible both to Cache
Managers and to other volume operations. Dumping a volume does not
otherwise affect its status on the partition or its VLDB entry.

To restore a dumped volume back into AFS, use the B<vos restore> command.

=head1 CAUTIONS

Support for incremental dumps is provided to facilitate interoperation
with third-party backup utilities. The B<vos dump> command does not
provide any of the administrative facilities of an actual backup system,
so the administrator must keep manual records of dump times and the
relationship between full and incremental dumps of a volume. For a
volume's contents to be consistent after restoration of incremental dumps,
there must be no gap between the time at which a prior dump of the volume
was created and the value of the B<-time> argument to the B<vos dump>
command that creates the incremental dump. More specifically, for a
read/write volume, the B<-time> argument must specify the time that the
prior dump was performed, and for a read-only or backup volume it must
specify the time that the volume was last released (using the B<vos
release> command) or cloned (using the B<vos backup> or B<vos backupsys>
command) prior to dumping it. The parent dump can be either a full dump or
another incremental dump.

=head1 OPTIONS

=over 4

=item B<-id> <I<volume name or ID>>

Specifies either the complete name or volume ID number of the read/write,
read-only, or backup volume to dump.

=item B<-time> <I<dump from time>>

Specifies whether the dump is full or incremental. Omit this argument to
create a full dump, or provide one of three acceptable values:

=over 4

=item *

The value C<0> (zero) to create a full dump.

=item *

A date in the format I<mm>B</>I<dd>B</>I<yyyy> (month, day and year) to
create an incremental dump that includes only files and directories with
modification timestamps later than midnight (12:00 a.m.) on the indicated
date. Valid values for the year range from C<1970> to C<2037>; higher
values are not valid because the latest possible date in the standard UNIX
representation is in 2038. The command interpreter automatically reduces
later dates to the maximum value. An example is C<01/13/1999>.

=item *

A date and time in the format B<">I<mm>B</>I<dd>B</>I<yyyy>
I<hh>B<:>I<MM>B<"> to create an incremental dump that includes only files
and directories with modification timestamps later than the specified date
and time. The date format is the same as for a date alone. Express the
time as hours and minutes (I<hh>:I<MM>) in 24-hour format (for example,
B<20:30> is 8:30 p.m.). Surround the entire expression with double quotes
(C<"">) because it contains a space.  An example is C<"01/13/1999 22:30">.

=back

=item B<-file> <I<dump file>>

Specifies the pathname of the file to which to write the dump. The file
can be in AFS, but not in the volume being dumped. A partial pathname is
interpreted relative to the current working directory. If this argument is
omitted, the dump is directed to the standard output stream.

=item B<-server> <I<server name>>

Specifies the file server machine on which the volume resides.  Provide
the B<-partition> argument along with this one.

=item B<-partition> <I<partition name>>

Specifies the partition on which the volume resides. Provide the
B<-server> argument along with this one.

=item B<-clone>

Normally, B<vos dump> locks the volume and dumps it, which blocks writes
to the volume while the dump is in progress.  If this flag is given, B<vos
dump> will instead clone the volume first (similar to what B<vos move>
would do) and then dumps the clone.  This can significantly decrease the
amount of time the volume is kept locked for dumps of large volumes.

=item B<-omitdirs>

By default, B<vos dump> includes all directory objects in an incremental
dump whether they've been changed or not.  If this option is given,
unchanged directories will be omitted.  This will reduce the size of the
dump and not cause problems if the incremental is restored, as expected,
on top of a volume containing the correct directory structure (such as one
created by restoring previous full and incremental dumps).

=item B<-cell> <I<cell name>

Names the cell in which to run the command. Do not combine this argument
with the B<-localauth> flag. For more details, see L<vos(1)>.

=item B<-noauth>

Assigns the unprivileged identity anonymous to the issuer. Do not combine
this flag with the B<-localauth> flag. For more details, see L<vos(1)>.

=item B<-localauth>

Constructs a server ticket using a key from the local
F</usr/afs/etc/KeyFile> file. The B<vos> command interpreter presents it
to the Volume Server and Volume Location Server during mutual
authentication. Do not combine this flag with the B<-cell> argument or
B<-noauth> flag. For more details, see L<vos(1)>.

=item B<-verbose>

Produces on the standard output stream a detailed trace of the command's
execution. If this argument is omitted, only warnings and error messages
appear.

=item B<-help>

Prints the online help for this command. All other valid options are
ignored.

=back

=head1 EXAMPLES

The following command writes a full dump of the volume C<user.terry> to
the file F</afs/abc.com/common/dumps/terry.dump>.

   % vos dump -id user.terry -time 0 -file /afs/abc.com/common/dumps/terry.dump

The following command writes an incremental dump of the volume
C<user.smith> to the file C<smith.990131.dump> in the current working
directory. Only those files in the volume with modification time stamps
later than 6:00 p.m. on 31 January 1999 are included in the dump.

   % vos dump -id user.smith -time "01/31/1999 18:00" -file smith.990131.dump

=head1 PRIVILEGE REQUIRED

The issuer must be listed in the F</usr/afs/etc/UserList> file on the
machine specified with the B<-server> argument and on each database server
machine. If the B<-localauth> flag is included, the issuer must instead be
logged on to a server machine as the local superuser C<root>.

If the B<-file> argument is included, the issuer must also have permission
to insert and write in the directory that houses the file.

=head1 SEE ALSO

L<restorevol(8)>,
L<vos(1)>,
L<vos_examine(1)>,
L<vos_listvldb(1)>,
L<vos_restore(1)>

=head1 COPYRIGHT

IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.

This documentation is covered by the IBM Public License Version 1.0.  It was
converted from HTML to POD by software written by Chas Williams and Russ
Allbery, based on work by Alf Wachsmann and Elizabeth Cassell.
