Forum Discussion

Fabian_Schwarz's avatar
Fabian_Schwarz
Level 4
10 years ago

Scratch tapes schema

Hi, 

Can you tell me which is the Netbackup schema to catch scratch tapes ?

7.5
Backup and Recovery
Linux
NetBackup
  • Nicolai's avatar
    Nicolai
    10 years ago

    You really dont need to worry.

    If a tape is being freed to re-use Netbackup will automaticaly re-use it.

    If the tape if full and put into the robot, Netbackup won't overwrite it before its free.

    How many tape per robot only you can tell. It all depen on may tape you use per day. But never go to 0 - Netbackup run best if you have "enough" fee tapes. Enough tapes depend on size, tape pools and retension. For some configuration 2 will be OK, for other 200 may be needed.

  • mph999's avatar
    mph999
    Level 6
    10 years ago

    Not sure I quite understand what you wish to ask ...

    Scratch tapes are just a special pool, that contain 'expired' or 'empty' tapes.  Other pools pull tapes from here as required.

    If a tape starts in scratch, is used (so changed to some other pool) and then expired, it will return to scratch.

    Tapes that start in another pool, eg. NetBackup, stay in that pool when expired - so for example, if I move a tape manually to NetBackup pool it stays there, even if expired.  If NetBackup pulls a tape from scratch, into the netbackup pool, then it returns to scratch when expired.

    Does that help ?

  • Nicolai's avatar
    Nicolai
    Moderator
    10 years ago

    Tech note - About scratch volume pools

    http://www.symantec.com/docs/HOWTO49122

    And you can only have once scratch pool.

     

  • Fabian_Schwarz's avatar
    Fabian_Schwarz
    Level 4
    10 years ago

    What I really need to know is when NBU catch a scratch tape (in the robotic library) to use in backups.

    Need I put scratch tapes in my robotic library when is zeroed (no scratch tapes), or can I wait until NBU

    uses all unfilled tapes (no full tapes) ?  

  • Marianne's avatar
    Marianne
    Level 6
    10 years ago
    If you simply need to list tapes in Scratch pool, run this command for tapes in robot 0: vmquery -rn 0 -bx | grep -i scratch If you need ALL tapes for specific density (e.g. hcart3) in scratch pool (including non-robotic): vmquery -a -bx | grep -i scratch | grep -i hcart3
  • Marianne's avatar
    Marianne
    Level 6
    10 years ago

    To know in advance when tape will expire and can be put back in the robot, use the 'Tape Summary' report in the GUI with 'verbose' option selected.
    Run this report once a week and save output.

    From cmd: 
    bpmedialist -summary -verbose

  • Marianne's avatar
    Marianne
    Level 6
    10 years ago

    It all depends on your config.

    If media sharing is configured, multiple media servers can write to the same tape.

    The NBU default is no media sharing.
    Each media server will be assigned ownership the first time it writes to a tape. Only that media server can now append to that tape.
    When all images ona tape have expired, any media server with access to the robot/media can write to media.

    (All documented in NBU Admin Guide I)

  • Marianne's avatar
    Marianne
    Level 6
    10 years ago

    You check configuration.

    For unrestricted media sharing:
     Host Properties > Master Servers.
     double-click the master server.
     Select Media
    Check if 'Enable Unrestricted Media Sharing for All Media Servers' is selected.

    For media sharing with a server group, check as follows:
    Expand Media and Device Management > Devices > Server Groups.
    See if any server groups are configured.
     

    All of the above is described in NetBackup Administrator's Guide, Volume I 

    Search for 'About media sharing'

  • Fabian_Schwarz's avatar
    Fabian_Schwarz
    Level 4
    10 years ago

    Can you tell me which´s the best moment to put scratch tapes in my robotic library ?

    (When it doesn´t haves no one scratch tape or when backup jobs fails with error 96) ?