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       backup_scantape - Extracts dump information from a tape


       backup scantape [-dbadd] [-portoffset <TC port offset>]
           [-localauth] [-cell <cell name>] [-help]

       backup sc [-d] [-p <TC port offset>] [-l]
           [-c <cell name>] [-h]


       The backup scantape command extracts information from the dump labels
       and volume headers on the tape in the device controlled by the Tape
       Coordinator indicated by the -portoffset argument. The Tape Coordinator
       displays the information for each volume in its window as soon as it
       extracts it (rather than waiting until it has scanned the entire tape).

       (If the "FILE YES" instruction appears in the
       /var/lib/openafs/backup/CFG_device_name file associated with the
       specified port offset, then the backup scantape command extracts dump
       information from the backup data file named in that port offset’s entry
       in the /var/lib/openafs/backup/tapeconfig file on the Tape Coordinator
       machine, rather than from 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.)

       If the -dbadd flag is provided, the backup scantape command creates new
       dump and volume records in the Backup Database for the scanned
       information. However, if it finds that a record already exists in the
       database for the same dump, it terminates the scanning operation.

       The scanning operation works only on tapes containing volume data.  The
       command fails with an error message if the tape contains a copy of the
       Backup Database (was created with the backup savedb command, or has the
       AFS tape name "Ubik_db_dump.1").

       The Tape Coordinator’s default response to this command is to access
       the tape by invoking the "MOUNT" instruction in the 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.

       To terminate a tape scanning operation in interactive mode, issue the
       backup kill command. In noninteractive mode, the only choice is to use
       a termination signal such as Ctrl-C to halt the Tape Coordinator


       A scanning operation does not have to begin with the first tape in a
       dump set, but the Backup System can process tapes only in sequential
       order after the initial tape provided. The Tape Coordinator
       automatically requests any subsequent tapes by invoking the "MOUNT"
       instruction in the local /var/lib/openafs/backup/CFG_device_name file,
       or by prompting the operator if there is no "MOUNT" instruction.

       The Tape Coordinator’s success in scanning a tape that is corrupted or
       damaged depends on the extent of the damage and what type of data is
       corrupted. It can almost always scan the tape successfully up to the
       point of damage. If the damage is minor, the Tape Coordinator can
       usually skip over it and scan the rest of the tape, but more major
       damage can prevent further scanning. Because a scanning operation can
       start on any tape in a dump set, damage on one tape does not prevent
       scanning of the others in the dump set. However, it is possible to scan
       either the tapes that precede the damaged one or the ones that follow
       it, but not both.

       If a tape is relabeled with the backup labeltape command, it is not
       possible to recover data from it for the purposes of rebuilding the
       Backup Database.

       If the -dbadd flag is included on the command, it is best not to
       terminate the tape scanning operation before it completes (for example,
       by issuing the backup kill command in interactive mode). The Backup
       System writes a new record in the Backup Database for each dump as soon
       as it scans the relevant information on the tape, and so it possibly
       has already written new records. If the operator wants to rerun the
       scanning operation, he or she must locate and remove the records
       created during the terminated operation: the second operation exits
       automatically if it finds that a record that it needs to create already

       If the -dbadd flag is included and the first tape provided is not the
       first tape in the dump set, the following restrictions apply:

       ·   If the first data on the tape is a continuation of a volume that
           begins on the previous (unscanned) tape in the dump set, the Backup
           System does not add a record for that volume to the Backup

       ·   The Backup System must read the marker that indicates the start of
           an appended dump to add database records for the volumes in it. If
           the first volume on the tape belongs to an appended dump, but is
           not immediately preceded by the appended-dump marker, the Backup
           System does not create a Backup Database record for it or any
           subsequent volumes that belong to that appended dump.


           Adds the information extracted from the tape to the Backup Database
           (but only if the database does not already contain an entry with
           the same dump ID number).

       -portoffset <TC port offset>
           Specifies the port offset number of the Tape Coordinator handling
           the tapes for this operation.

           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).

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


       For every dump on a tape, the backup scantape command displays in the
       Tape Coordinator window the dump label and the volume header of each
       volume in the dump. If a dump spans more than one tape, the dump label
       does not repeat at the beginning of subsequent tapes.

       A dump label contains the following fields, which are the same as in
       the output from the backup readlabel command:

       tape name
           The permanent name assigned by using the -pname argument of the
           backup labeltape command. This name remains on the tape until that
           argument is used again, no matter how many times the tape is
           recycled or otherwise relabeled. If the tape does not have a
           permanent name, the value "<NULL>" appears in this field.

       AFS tape name
           A tape name in one of the following prescribed formats. The Backup
           System automatically writes the appropriate AFS tape name to the
           label as part of a backup dump operation, or the operator can
           assign it with the -name argument to the backup labeltape command.

           ·   volume_set_name.dump_level_name.tape_index, if the tape
               contains volume data. The volume_set_name is the name of the
               volume set that was dumped to create the initial dump in the
               dump set of which this tape is a part; dump_level_name is the
               last pathname element of the dump level at which the initial
               dump was backed up; and tape_index is the numerical position of
               the tape in the dump set.

           ·   "<NULL>" if the tape has no AFS tape name. This is normally the
               case if the -name argument was not included the last time the
               backup labeltape command was used on this tape, and no data has
               been written to it since.

           The date and time at which the Backup System started performing the
           dump operation that created the initial dump.

           The cell in which the dump set was created. This is the cell whose
           Backup Database contains a record of the dump set.

           The tape’s capacity (in kilobytes) as recorded on the label, rather
           than the amount of data on the tape. The value is assigned by the
           -size argument to the backup labeltape command or derived from the
           /var/lib/openafs/backup/tapeconfig file on the Tape Coordinator
           machine, not from a measurement of the tape.

       dump path
           The dump level of the initial dump in the dump set.

       dump id
           The dump ID number of the initial dump in the dump set, as recorded
           in the Backup Database.

           The number of times a dump has been written to the tape, or it has
           been relabeled.

       The volume header contains the following fields:

       volume name
           The volume name, complete with a ".backup" or ".readonly"
           extension, if appropriate.

       volume ID
           The volume’s volume ID.

           The dump to which the volume belongs. The dump name is of the form
           volume_set_name.dump_level_name and matches the name displayed in
           the dump label.

           The dump ID of the dump named in the "dumpSetName" field.

           The depth in the dump hierarchy of the dump level used in creating
           the dump. A value of 0 indicates a full dump. A value of 1 or
           greater indicates an incremental dump made at the indicated depth
           in the hierarchy. The value reported is for the entire dump, not
           necessarily for the volume itself; for example, it is possible for
           a dump performed at an incremental level to include a full dump of
           an individual volume if the volume was omitted from previous dumps.

           The dump ID number of "dumpSetName"’s parent dump. It is 0 if the
           value in the "level" field is 0.

           Is always 0; it is reserved for internal use.

           The date and time at which the volume was created. For a backup or
           read-only volume, this represents the time at which it was cloned
           from its read/write source. For a read/write volume, it indicates
           the time at which the Backup System locked the volume for purposes
           of including it in the dump named in the "dumpSetName" field.

       The message "Scantape: Finished" indicates the completion of the

       In normal circumstances, the Backup System writes a marker to indicate
       that a volume is the last one on a tape, or that the volume continues
       on the next tape. However, if a backup operation terminated abnormally
       (for example, because the operator terminated the Tape Coordinator by
       issuing the Ctrl-C command during the operation), then there is no such
       marker. Some very early versions of the Backup System also did not
       write these markers. If a tape does not conclude with one of the
       expected markers, the Tape Coordinator cannot determine if there is a
       subsequent tape in the dump set and so generates the following message
       in its window:

          Are there more tapes? (y/n)


       The following example shows the output for the first two volumes on a
       tape in the device with port offset 0:

          % backup scantape
          Dump label
          tape name = monthly_guest
          AFS tape name = guests.monthly.3
          creationTime =  Mon Feb  1 04:06:40 1999
          cell =
          size = 2150000 Kbytes
          dump path = /monthly
          dump id = 917860000
          useCount = 44
          -- End of dump label --
          -- volume --
          volume name: user.guest10.backup
          volume ID 1937573829
          dumpSetName: guests.monthly
          dumpID 917860000
          level 0
          parentID 0
          endTime 0
          clonedate Mon Feb  1 03:03:23 1999
          -- volume --
          volume name: user.guest11.backup
          volume ID 1938519386
          dumpSetName: guests.monthly
          dumpID 917860000
          level 0
          parentID 0
          endTime 0
          clonedate Mon Feb  1 03:05:15 1999


       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.


       butc(5), backup(8), backup_dump(8), backup_dumpinfo(8), butc(8)


       IBM Corporation 2000. <> 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.