=head1 NAME

vos - Introduction to the vos command suite

=head1 DESCRIPTION

The commands in the B<vos> command suite are the administrative interface
to the Volume Server and Volume Location (VL) Server. System
administrators use B<vos> commands to create, move, delete, replicate,
back up and examine volumes, among other operations. The VL Server
automatically records in the Volume Location Database (VLDB) changes in
volume status and location that result from B<vos> commands.

The operations invoked by most B<vos> commands are idempotent, meaning
that if an operation is interrupted by a network, server machine, or
process outage, then a subsequent attempt at the same operation continues
from the interruption point, rather than starting over at the beginning of
the operation. Before executing a command, the Volume and VL Servers check
the current state of the volumes and VLDB records to be altered by the
command. If they are already in the desired end state (or a consistent
intermediate state), there is no need to repeat the internal steps that
brought them there. Idempotency does not apply if the command issuer
explicitly interrupts the operation with the Ctrl-C command or another
interrupt signal. In that case, the volume is left locked and the
administrator must use the L<B<vos unlock>|vos_unlock(1)> command to
unlock it before proceeding.

It is important that the VLDB accurately indicate the status of the
volumes on file server machines at all times. L<vldb.DB0(5)> and
L<afs_volume_header(5)> describe the information recorded in the VLDB and
volume headers, respectively. If a B<vos> command changes volume status,
it automatically records the change in the corresponding VLDB entry. The
most common cause of discrepancies between the VLDB and volume status on
file server machines is interrupted operations; to restore consistency,
use the L<B<vos syncserv>|vos_syncserv(1)> and
L<B<vos syncvldb>|vos_syncvldb(1)> commands.

There are several categories of commands in the vos command suite:

=over 4

=item *

Commands to create, move, and rename volumes:
L<B<vos backup>|vos_backup(1)>,
L<B<vos backupsys>|vos_backupsys(1)>,
L<B<vos changeloc>|vos_changeloc(1)>,
L<B<vos create>|vos_create(1)>,
L<B<vos move>|vos_move(1)>,
and L<B<vos rename>|vos_rename(1)>.

=item *

Commands to remove VLDB volume records or volumes or both:
L<B<vos delentry>|vos_delentry(1)>,
L<B<vos remove>|vos_remove(1)>,
and L<B<vos zap>|vos_zap(1)>.

=item *

Commands to edit or display VLDB server entries:
L<B<vos changeaddr>|vos_changeaddr(1)>,
L<B<vos listaddrs>|vos_listaddrs(1)>
and L<B<vos setaddrs>|vos_setaddrs(1)>.

=item *

Commands to create, size, and restore dump files:
L<B<vos dump>|vos_dump(1)>,
L<B<vos restore>|vos_restore(1)>,
and L<B<vos size>|vos_size(1)>.

=item *

Commands to administer replicated volumes:
L<B<vos addsite>|vos_addsite(1)>,
L<B<vos release>|vos_release(1)>,
and L<B<vos remsite>|vos_remsite(1)>.

=item *

Commands to display VLDB records, volume headers, or both:
L<B<vos examine>|vos_examine(1)>,
L<B<vos listvldb>|vos_listvldb(1)>,
and L<B<vos listvol>|vos_listvol(1)>.

=item *

Commands to display information about partitions that house volumes:
L<B<vos listpart>|vos_listpart(1)>
and L<B<vos partinfo>|vos_partinfo(1)>.

=item *

Commands to restore consistency between the VLDB and volume headers:
L<B<vos syncserv>|vos_syncserv(1)>
and L<B<vos syncvldb>|vos_syncvldb(1)>.

=item *

Commands to lock and unlock VLDB entries:
L<B<vos lock>|vos_lock(1)>,
L<B<vos unlock>|vos_unlock(1)>,
and L<B<vos unlockvldb>|vos_unlockvldb(1)>.

=item *

A command to report Volume Server status:
L<B<vos status>|vos_status(1)>.

=item *

A command to end Volume Server transactions:
L<B<vos endtrans>|vos_endtrans(1)>.

=item *

A command to change volume fields:
L<B<vos setfields>|vos_setfields(1)>.

=item *

Commands to obtain help:
L<B<vos apropos>|vos_apropos(1)>
and L<B<vos help>|vos_help(1)>.

=back

=head1 CAUTIONS

Currently, the maximum size of a volume is 2 terabytes (2^31 bytes).

=head1 OPTIONS

The following arguments and flags are available on many commands in the
B<vos> suite. The reference page for each command also lists them, but
they are described here in greater detail.

=over 4

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

Names the cell in which to run the command. It is acceptable to abbreviate
the cell name to the shortest form that distinguishes it from the other
entries in the F</usr/vice/etc/CellServDB> file on the local machine. If
the B<-cell> argument is omitted, the command interpreter determines the
name of the local cell by reading the following in order:

=over 4

=item *

The value of the AFSCELL environment variable.

=item *

The local F</usr/vice/etc/ThisCell> file.

=back

Do not combine the B<-cell> and B<-localauth> options. A command on which
the B<-localauth> flag is included always runs in the local cell (as
defined in the server machine's local F</usr/afs/etc/ThisCell> file),
whereas a command on which the B<-cell> argument is included runs in the
specified foreign cell.

=item B<-config> <I<config directory>>

The location of the directory to use to obtain configuration information,
including the CellServDB. This is primarily provided for testing purposes.

=item B<-help>

Prints a command's online help message on the standard output stream. Do
not combine this flag with any of the command's other options; when it is
provided, the command interpreter ignores all other options, and only
prints the help message.

=item B<-localauth>

Constructs a server ticket using the server encryption key with the
highest key version number in the local F</usr/afs/etc/KeyFile> file. The
B<vos> command interpreter presents the ticket, which never expires, to
the Volume Server and VL Server during mutual authentication.

Use this flag only when issuing a command on a server machine; client
machines do not usually have a F</usr/afs/etc/KeyFile> file.  The issuer
of a command that includes this flag must be logged on to the server
machine as the local superuser C<root>. The flag is useful for commands
invoked by an unattended application program, such as a process controlled
by the UNIX B<cron> utility or by a cron entry in the machine's
F</usr/afs/local/BosConfig> file. It is also useful if an administrator is
unable to authenticate to AFS but is logged in as the local superuser
B<root>.

Do not combine the B<-cell> and B<-localauth> options. A command on which
the B<-localauth> flag is included always runs in the local cell (as
defined in the server machine's local F</usr/afs/etc/ThisCell> file),
whereas a command on which the B<-cell> argument is included runs in the
specified foreign cell. Also, do not combine the B<-localauth> and
B<-noauth> flags.

=item B<-noauth>

Establishes an unauthenticated connection to the Volume Server and VL
Server, in which the servers treat the issuer as the unprivileged user
C<anonymous>. It is useful only when authorization checking is disabled on
the server machine (during the installation of a file server machine or
when the L<B<bos setauth>|bos_setauth(8)> command has been used during
other unusual circumstances). In normal circumstances, the servers allow
only privileged users to issue commands that change the status of a volume
or VLDB record, and refuses to perform such an action even if the
B<-noauth> flag is provided. Do not combine the B<-noauth> and
B<-localauth> flags.

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

Identifies the AFS server partition on a file server machine that houses,
or is to house, the volumes of interest, or about which to list
information. The B<vos> command interpreter accepts any of the following
four name formats:

   /vicepa     =     vicepa      =      a      =      0
   /vicepb     =     vicepb      =      b      =      1

After /vicepz (for which the index is 25) comes

   /vicepaa    =     vicepaa     =      aa     =      26
   /vicepab    =     vicepab     =      ab     =      27

and so on through

   /vicepiv    =     vicepiv     =      iv     =      255

The B<-frompartition> and B<-topartition> arguments to the
L<B<vos move>|vos_move(1)> command also accept this notation.

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

Identifies the file server machine that houses, or is to house, the
volumes or AFS server partitions of interest. Provide the machine's IP
address in dotted decimal format, its fully qualified host name (for
example, C<fs1.example.com>), or the shortest abbreviated form of its host
name that distinguishes it from other machines. Successful use of an
abbreviated form depends on the availability of a name resolution service
(such as the Domain Name Service or a local host table) at the time the
command is issued.

The B<-fromserver> and B<-toserver> arguments to the
L<B<vos move>|vos_move(1)> command also accept these name formats.

=item B<-noresolve>

Shows all servers as IP addresses instead of the DNS name. This is very
useful when the server address is registered as 127.0.0.1 or when dealing
with multi-homed servers. The B<-noresolve> option is available in OpenAFS
versions 1.4.8 or later and 1.5.35 or later.

=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.

=back

=head1 PRIVILEGE REQUIRED

To issue most vos commands, the issuer must be listed in the
F</usr/afs/etc/UserList> file on each server machine that houses or is to
house an affected volume, and on each database server machine. The most
predictable performance results if all database server and file server
machines in the cell share a common F<UserList> file.  Alternatively, if
the B<-localauth> flag is included, the issuer must be logged on to a
server machine as the local superuser C<root>.

To issue a vos command that only displays information, no privilege is
required.

=head1 SEE ALSO

L<vos_addsite(1)>,
L<vos_apropos(1)>,
L<vos_backup(1)>,
L<vos_backupsys(1)>,
L<vos_changeaddr(1)>,
L<vos_convertROtoRW(1)>,
L<vos_clone(1)>,
L<vos_copy(1)>,
L<vos_create(1)>,
L<vos_delentry(1)>,
L<vos_dump(1)>,
L<vos_endtrans(1)>,
L<vos_examine(1)>,
L<vos_help(1)>,
L<vos_listaddrs(1)>,
L<vos_listpart(1)>,
L<vos_listvldb(1)>,
L<vos_listvol(1)>,
L<vos_lock(1)>,
L<vos_move(1)>,
L<vos_partinfo(1)>,
L<vos_release(1)>,
L<vos_remove(1)>,
L<vos_remsite(1)>,
L<vos_rename(1)>,
L<vos_restore(1)>,
L<vos_setfields(1)>,
L<vos_shadow(1)>,
L<vos_size(1)>,
L<vos_status(1)>,
L<vos_syncserv(1)>,
L<vos_syncvldb(1)>,
L<vos_unlock(1)>,
L<vos_unlockvldb(1)>,
L<vos_zap(1)>,
L<CellServDB(5)>,
L<UserList(5)>

=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.
