Checking and Labeling Tape Media

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Copyright © SEP AG 1999-2017. All rights reserved.

Any form of reproduction of the contents or parts of this manual is allowed only with the express written permission from SEP AG. When compiling and designing user documentation SEP AG uses great diligence and attempts to deliver accurate and correct information. However, SEP AG cannot issue a guarantee for the contents of this manual.

Docs latest icon.png Welcome to the latest SEP sesam documentation version 4.4.3. For previous documentation version(s), check Documentation archive.


Overview

Each medium, whether a tape cartridge or a virtual tape in a VTL, is given a unique label for identification. The label is written to the beginning of a medium during the initialization. The medium label consists of the pool name (e.g., DAY, WEEK, MONTH) and a five-digit number that is automatically assigned to the respective media of the selected pool by SEP sesam. For example, a tape in the media pool DAY is labelled as DAY00001.

Manually identifying and relabeling tapes

You can check a tape label using the sm_drive info <drive_no.> command or the SEP sesam GUI.

  1. To check the label using the CLI, set the SEP sesam command environment and enter the command:
  2. sm_drive info <drive_no.>
    

    In our example, check the drive 1:

    sm_drive info 1
    

    Alternatively, you can also use the sm_sms_interface getlabel command which displays more information about the label (such as the creation date); for details, see FAQ: How can I determine whether a tape is a SEP sesam tape or not?

    Or, to check the tape label using the GUI, click on Components -> Drives -> select the drive -> Drive action -> Identify label -> Start.

    Drive-identify label.png


  3. Then start the initialization and relabeling. This step must be done using the CLI. If you have not set the SEP sesam profile yet, you have to create it now so that SEP sesam commands can be executed globally. For details, see What happens when I set a profile?
  4. In the command line, execute the sm_drive init command. Attention: The tape will be overwritten without warning!
  5. sm_drive init <drive_no.> <label>
    

    In our example, insert the media in drive 1 with label DAY00001. Attention: The number must contain 5 digits!

    sm_drive init 1 DAY00001
    
    For alternative way of manually writing a label to tape, see FAQ: How can I manually write a label on a tape?

Usage scenario

In the standalone tape drive environment it might happen that multiple tapes are incorrectly marked with the same label. This happens because SEP sesam uses the get_oldest strategy to preserve the data on the tapes for the longest possible time. It automatically detects the oldest EOL-free medium and designates the label of the tape which is to be re-used next, e.g., DAY00004. When an alternate EOL-free tape is already inserted in a single tape drive, SEP sesam checks its label and detects a label mismatch. If the EOL of the inserted tape is not expired, SEP sesam will not use the tape. However, if the tape is EOL-free, SEP sesam will initialize it with the original (requested) label even though it may belong to another media pool and has its own label, e.g., MONTH00009. In such a case, a tape from another media pool may be accidentally overwritten if it is already EOL-free. This problem occurred in SEP sesam version 4.4.3.25 and was resolved by a service pack. For details, see Release Notes 4.4.3 – Known issues and limitations.

Resolving label conflicts

To resolve conflicts with duplicate media labels and avoid problems with potential data loss, you have to manually identify the tape with the original label that was duplicated, insert it in the stand-alone drive and relabel it with the original label of the second tape. Then you have to manually change the stick-on label or slide-in label (paper or card) on the front of both tapes. This way you will ensure that the newly written backup data will not be overwritten.

Example: Label MONTH00009 was overwritten with label DAY00004.

  1. Insert the tape that was original labeled DAY00004 and relabel it to MONTH00009. For details, see above procedure.
  2. Remove the label DAY00004 from the tape and stick the mismatched label MONTH00009 to it. Then put the label DAY00004 onto the newly written tape (formerly MONTH00009).

See also

Setting SEP sesam profileFAQ: How can I determine whether a tape is a SEP sesam tape or not? - FAQ: How can I manually write a label on a tape?Used Tapes of a Sesam DayMediaLoadersDrives