Example of How to Back Up your Data Files

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Let's say I want to back up all my UV data files on disk 2 of RGLINUX4. My steps are as follows:

  1. Run the AIPS task DISKU by typing the following lines:

    restore 0 task 'disku' indisk=2; sort='b'; doall=1 inp go
    Note: Restore 0 resets all inputs to their default values. You then need only set a few crucial inputs (the ones given here) and not worry if the others are correct or not.

    Wait till the task has completed and at the bottom of your screen output, you will see some summarized information similar to the following:

    User Images UV files Extensions Other Total
    # # blocks # blocks # blocks # blocks blocks
    999 74 4736 24 3929236 685 165510 1 5 4099487

    The above three lines say that I (userid=999) have:

    74 Image files taking up 4736 blocks 24 UV data files taking up 3929236 blocks 685 Extensions taking up 165510 blocks

  2. Convert blocks to GB as follows:

    3,929,236 / 1,000,000 = 3.9 GB 3.9 x 3 = 11.7 GB (because FILETYPE='UV')

    The DATs, EXABYTEs, and DLTs page says that only a DLT (or DDS 4 DAT) will be large enough to accommodate all 24 files. At this point ask yourself if it is really necessary to keep all 24 files. If not, delete the unnecessary ones and rerun DISKU.

    My advice is to:

    Always use the smallest backup medium that will accommodate your data. Clean up your disk. Delete unnecessary files (intermediate and test files) before backing up.

    Note: I have not included the Extension files (e.g., CLs, CCs). Some belong to the UV data files and some to the image files. They are small and for rough size estimates do not need to be included.

  3. Physically mount your DLT in the RGLINUX4 tape drive. Remember to set density=40.0 on the left hand panel of the drive and make sure the compress light is off.
  4. Software mount your DLT with the AIPS task MOUNT by typing:

    restore 0 intape=3 inp mount mount

  5. Write data files to tape with the AIPS task FITTP by typing:

    restore 0 task 'fittp' doall=1; indisk=2; intype='uv'; outtape=3; doeot=-1 inp go

  6. Issue the DISMOUNT command within AIPS and remove your DLT from the drive. Don't forget to wait a few seconds before yanking it out.
  7. Set the write protector switch, i.e., the orange indicator should be visible.

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