What does 'Mark as Free' do?

[acatic]

Noob question, but a concrete answer has eluded me:

What exactly does 'Mark as Free' do?

It reportedly does not erase the data on the tape, instead just showing the tape as empty and marking it as usable.

Are its contents still restorable if not written to again, then?

If a job starts writing to it, does it start from the beginning of the tape, overwriting as it goes along? Or, does it append first?

What is the difference between 'Mark as Free' and a quick erase? Not much difference time-wise, so is one preferred over the other in certain circumstances? If I plan to get rid of or downgrade a tape, I do a full/long delete.

Thank you for enlightenment on this matter.

[HannesK]

Hello,
as you already mentioned, it does not erase. From user guide

Instead of erasing tapes, you can mark tapes as free. During this operation, Veeam Backup & Replication deletes from backup and tape catalogs information about backup contents stored on tape. Data written to tape remains intact.

If a job wants to write to that tape, it starts from the beginning and overwrites the data.

About the difference, see the quote above and the quote from here

The short erase operation does not physically erase data written on the tape. It simply loads the tape to the drive and wipes the tape header.

Does that help you?

Best regards,
Hannes

[veremin]

Are its contents still restorable if not written to again, then?

Correct, you can then re-catalog tape and see the data residing there.

If a job starts writing to it, does it start from the beginning of the tape, overwriting as it goes along?

From the beginning.

Thanks!