backup_labeltape

Langue: en

Version: 2007-11-11 (debian - 07/07/09)

Section: 8 (Commandes administrateur)

NAME

backup_labeltape - Creates the magnetic label on a tape

SYNOPSIS

backup labeltape [-name <AFS tape name, defaults to NULL>]
    [-size <tape size in Kbytes, defaults to size in tapeconfig>]
    [-portoffset <TC port offset>] [-pname <permanent tape name>]
    [-localauth] [-cell <cell name>] [-help]

backup la [-n <AFS tape name, defaults to NULL>]
    [-s <tape size in Kbytes, defaults to size in tapeconfig>]
    [-po <TC port offset>] [-pn <permanent tape name>]
    [-l] [-c <cell name>] [-h]

DESCRIPTION

The backup labeltape command creates a magnetic label, readable by the Backup System, at the beginning of a tape. The label records the tape's name (either a permanent name, or an AFS tape name that reflects the tape's contents in a prescribed format) and its capacity.

(If the "FILE YES" instruction appears in the /var/lib/openafs/backup/CFG_device_name file on the Tape Coordinator machine associated with the specified port offset, then the backup command writes label information to the first 16 KB block in the backup data file listed for that port offset in the Tape Coordinator's /var/lib/openafs/backup/tapeconfig file, rather than at the beginning of a tape. For the sake of clarity, the following text refers to tapes only, but the Backup System handles backup data files in much the same way.)

Relabeling a tape that already contains AFS backup data effectively makes the data unusable, because the command removes the Backup Database record of the complete dump set of which the tape is a part. Use this command to enable recycling of a tape that contains unexpired dumps that are not actually still needed.

To write a permanent name on the label, include the -pname argument to specify a string of up to 32 characters. The permanent name persists until the -pname argument is again included on the backup labeltape command, regardless of the tape's contents and of how often the tape is otherwise relabeled or recycled. Include this argument or the -name argument, but not both. If this argument is included, the AFS tape name is set to "<NULL>". The permanent name is set to "<NULL>" if this argument is omitted and no permanent name already exists.

The issuer must ensure that a permanent name is unique among the tapes used for AFS backup in the cell, because the backup command interpreter does not verify that another tape does not already have the same permanent name. When a tape has a permanent name, the Backup System uses it instead of the AFS tape name in most prompts and when referring to the tape in output from backup commands. The permanent name appears in the "tape name" field of the output from the backup readlabel command.

To write an AFS tape name on the label, provide a value for the -name argument in the required format described in OPTIONS. Include the -name argument or the -pname argument, but not both. If this argument is omitted, the AFS tape name is set to "<NULL>", but the Backup System automatically assigns the appropriate name when the tape is used in a future backup dump or backup savedb operation. The AFS tape name appears in the "AFS tape name" field of the output from the backup readlabel and backup scantape commands.

The backup command interpreter does not accept the -name argument if the tape already has a permanent name. To erase a tape's permanent name, provide a null value to the -pname argument by issuing the following command:

    % backup labeltape -pname ""
 
 

To record the tape's capacity on the label, specify a number of kilobytes as the -size argument. If the argument is omitted the first time a tape is labeled, the Backup System records the default tape capacity recorded for the specified port offset in the /var/lib/openafs/backup/tapeconfig file on the Tape Coordinator machine. Subsequently, the value in the size field persists until the -size argument is again included on the backup labeltape command.

To determine how much data can be written to a tape during a backup dump or backup savedb operation, the Tape Coordinator reads the capacity recorded on the tape's label (or uses the value associated with its port offset in the /var/lib/openafs/backup/tapeconfig file, if the tape was never labeled). For further description, see the backup dump reference page.

The Tape Coordinator's default response to this command is to access the tape by invoking the "MOUNT" instruction in the local /var/lib/openafs/backup/CFG_device_name file, or by prompting the backup operator to insert the tape if there is no "MOUNT" instruction. However, if the "AUTOQUERY NO" instruction appears in the CFG_device_name file, or if the issuer of the butc command included the -noautoquery flag, the Tape Coordinator instead expects the tape to be in the device already. If it is not, the Tape Coordinator invokes the "MOUNT" instruction or prompts the operator.

OPTIONS

-name <AFS tape name>
Specifies the AFS tape name to record on the label. Include this argument or the -pname argument, but not both. If this argument is omitted, the AFS tape name is set to "<NULL>". If this argument is provided, it must have the following format:
    <volume_set_name>.<dump_level_name>.<tape_index>
 
 

for the tape to be acceptable for use in a future backup dump operation. The <volume_set_name> must match the volume set name of the initial dump to be written to the tape, <dump_level_name> must match the last element of the dump level pathname at which the volume set will be dumped, and <tape_index> indicates the order of the tape in the dump set (indexing begins with 1). To disable this type of name checking, include the "NAME_CHECK NO" instruction in the CFG_device_name file.

For the tape to be acceptable for use in a future backup savedb operation, the value specified for the -name argument must have the following format:

    Ubik_db_dump.<tape_index>
 
 

where <tape_index> indicates the order of the tape in the set of tapes that house the Backup Database dump; indexing begins with 1 (one).

-size <tape size>
Specifies the tape capacity to record on the label. Provide an integer value followed by a letter that indicates units, with no intervening space. A unit value of "k" or "K" indicates kilobytes, "m" or "M" indicates megabytes, and "g" or "G" indicates gigabytes. If the units letter is omitted, the default is kilobytes.

If this argument is omitted the first time a tape is labeled, the Backup System records the capacity that is associated with the specified port offset in the /var/lib/openafs/backup/tapeconfig file on the Tape Coordinator machine. The value recorded the first time then persists until the -size argument is provided on a future issuance of the command.

-portoffset <TC port offset>
Specifies the port offset number of the Tape Coordinator handling the tape for this operation.
-pname <permanent tape name>
Specifies the permanent name to record on the label. It can be up to 32 characters in length, and include any alphanumeric characters. Avoid metacharacters that have a special meaning to the shell, to avoid having to mark them as literal in commands issued at the shell prompt.

Include this argument or the -name argument, but not both. If this argument is provided, the AFS tape name is set to "<NULL>". If this argument is omitted, any existing permanent name is retained.

-localauth
Constructs a server ticket using a key from the local /etc/openafs/server/KeyFile file. The backup command interpreter presents it to the Backup Server, Volume Server and VL Server during mutual authentication. Do not combine this flag with the -cell argument. For more details, see backup(8).
-cell <cell name>
Names the cell in which to run the command. Do not combine this argument with the -localauth flag. For more details, see backup(8).
-help
Prints the online help for this command. All other valid options are ignored.

EXAMPLES

The following command records the AFS tape name "user.monthly.1" on the label of the tape in the device with port offset 3:
    % backup labeltape -name user.monthly.1 -portoffset 3
 
 

The following three commands are equivalent in effect: they all record a capacity of 2 GB on the label of the tape in the device with port offset 4. They set the AFS tape name to "<NULL>" and leave the permanent name unchanged.

    % backup labeltape -size 2g -portoffset 4
    % backup labeltape -size 2048M -portoffset 4
    % backup labeltape -size 2097152 -portoffset 4
 
 

PRIVILEGE REQUIRED

The issuer must be listed in the /etc/openafs/server/UserList file on every machine where the Backup Server is running, or must be logged onto a server machine as the local superuser "root" if the -localauth flag is included.

SEE ALSO

butc(5), backup(8), backup_readlabel(8), butc(8) 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.