Restoring from a mediaset spanning multiple harddrives

[barup]

Setup:

An archiving mediaset spanning multiple 8TB external harddrives.

When we try to restore files from this archive, the restore process doesn't tell which of the drives it needs.

Is there a way to get that info ?

 

kind regards

Lars

[DavidHertzberg]

I don't archive, and I Recycle each of my rotating Media Sets every three weeks, so I've never been faced with this problem.  However I think barup should look at this YouTube video, especially from minute:second 0:20 to 2:25.  Unfortunately Retrospect Inc. only made a version of that video for Retrospect Windows, so barup will have to get used to Media Sets being referred to as Backup Sets and other UI differences.  The equivalent operation is documented on pages 128-130 of the Retrospect Mac 14 User's Guide.

My basic idea is that, by searching for at least some the file/folder names he/she wants to Restore, barup will be able to see the dates on which those files were written to the Backup Set used for archiving.  That should give him/her an idea which drives are needed.  If the drives haven't been externally labeled with the dates they span, he/she can look at the creation and last-updated dates of the the Media Set members (the files that start with a number followed by a dash within the folder for the Media Set within the Retrospect folder) on them using Get Info.

[barup]

I'm just puzzled, why there are no way to see where the file is located, if it spans multiple mediaset members.

[DavidHertzberg]

If barup thinks this is a feature that should be added to Retrospect, here is why and how to submit a Support Case.

If barup would be satisfied with seeing the date a file was last updated, as a clue to which member of the archive Media Set it is on, it appears—contrary to what I said in my previous post in this thread—that he/she must do it via the user-initiated Restore facility described on page 75 of the Retrospect Mac 14 User's Guide.  To be sure he/she is accessing the Catalog File for the archive, he/she must do this by accessing System Preferences->Retrospect->History—so as to see the name of the Media Set—before clicking the lock icon and entering the password and then clicking the Restore button for that Media Set.

What concerns me is the reason barup would think this feature is needed.  For no more than about US$55, one can buy a hub with 7 ports on which to attach USB3 external drives, which would allow barup to simultaneously attach 56TB of storage for 8TB-disk Members of the archive Media Set.  If barup has more than 7 Members in his archive Media Set, IMHO he/she should be considering using LTO-8 tape instead of disk.  Assuming the price of an LTO-8 tape drive soon drops from its current US$3000 down to the US$2000 price for previous-generation LTO drives, while the price of a good 8TB USB3 disk drive stays around US$300, the cost crossover point will soon be around 8 Members.  Of course using a tape drive for a Restore would require someone to feed the tapes in succession into the drive, but the tradeoff is that tapes are generally assumed to have a longer lifetime than seldom-used disk drives.  As an experiment, a couple of years ago I successfully restored some files from a 12-year-old set of DDS tapes (colloquially known as DAT tapes from their Digital Audio Tape ancestor) ; the tapes had been kept under ideal conditions in a bank safe deposit box, but the DDS drive that read the tapes had been sitting on my shelf for about 12 years.  The uncompressed capacity of an LTO-8 tape is 12 TB.

Edited January 10, 2018 by DavidHertzberg
using a tape drive for a Restore would require someone to feed the tapes in succession into the drive; WP link for DDS tape

[DavidHertzberg]

barup,

If you actually submitted a Support Case for an enhancement, you got your wish with Restore Preflight in Retrospect Mac 17.0.