Naming the tapes ahead of time may or may not work, depending on the state
of the autoloader and when the media request occurs. There is a flaw in
Retrospect's logic when choosing tapes from a loader. This is a complex
issue, so please read this carefully.

Also, we consider this a bug, and we will correct this behavior in future
releases of both Mac and Windows products.


RETROSPECT, AUTOLOADERS, AND ERASED MEDIA

If all tapes are known then Retrospect does not use the properly pre-named
tape if it's erased and instead uses the first or last blank one.

In both Mac & Windows products, Retrospect will always use the pre-named
tape if it has to search the loader for tape names, regardless of whether
the pre-named tape is erased or has Retrospect data on it. However, if the
tape names are known (already scanned), Retrospect will use the pre-named
tape if it's got Retrospect data on it but will use the first (Mac
Retrospect) or last (Win Retrospect) erased/unnamed tape if the pre-named
tape is erased.


EXAMPLES

In the following scenarios, there are 3 tapes in the loader slots in this
order: erased tape/no name, erased or non-erased tape/pre-named, erased
tape/no name.

We run a scripted backup to these tapes in two loader states: 1) tapes are
scanned and known (i.e., tape names are displayed in the UI); 2) tapes are
not scanned and are unknown (i.e., tapes names display "?" or "Unknown").

(On the Mac, Retrospect will almost always have to search all the tapes
since memory of the tape names is not retained after re-launching.)

Retrospect for Windows 5.11
All known tapes w/ non-erased, pre-named tape: Uses the pre-named tape. All
known tapes w/ erased, pre-named tape: Uses the last erased tape found .

Unscanned tapes w/ non-erased, pre-named tape: Uses the pre-named tape.
Unscanned tapes w/ erased, pre-named tape: Uses the pre-named tape.

Retrospect for Macintosh 4.2
All known tapes w/ non-erased, pre-named tape: Uses the pre-named tape. All
known tapes w/ erased, pre-named tape: Uses the first erased tape found.

Unscanned tapes w/ non-erased, pre-named tape: Uses the pre-named tape.
Unscanned tapes w/ erased, pre-named tape: Uses the pre-named tape.


In a poor man's loader (two or more single cartridge tape drives),
Retrospect always chooses the pre-named tape whether it's erased or has
Retrospect data on it. If both are erased, the Mac & Windows product will
use the drive with the higher SCSI ID number.

I hope this sufficiently explains which piece of media Retrospect will
choose in various situations.

Best regards,

Eric Ullman
Dantz Development



Noah Eiger <[EMAIL PROTECTED]> wrote:

> Thanks for the tips. Does this mean that the method of "naming" the
> tapes ahead of time will NOT work? Does Retro look for an erased tape
> or an untitled tape?
> 
>> Hi Noah,
>> 
>> Retrospect will label erased tapes as it sees fit. If a tape is erased,
>> Retrospect ignores the tape's name. Retrospect will only look for a tape by
>> name once that tape has already been written to.
>> 
>> Your specific experience will differ if you are running a regular backup
>> script or a Backup Server script. Regular, scripted operations will ask for
>> tapes based on the specific scheduled operations you have set.
>> 
>> A Backup Server script, when instructed to use multiple backup sets, will
>> dynamically prioritize the media based on its own assessment of the
>> available backup sets. In an autoloader, when erased media is available,
>> Backup Server will assign the tapes to more than one backup set and rotate
>> between them automatically.
>> 
>> It's generally best to label the media *after* Retrospect decides what to
>> name each tape.
>> 
>> We also have a Backup Server FAQ which will should make its functionality
>> easier to understand.
>> 
>> http://www.dantz.com/index.php3?SCREEN=bscommonq
>> 
>> Best regards,
>> 
>> Eric Ullman
>> Dantz Development
>> 
>> 
>> Noah Eiger <[EMAIL PROTECTED]> wrote:
>> 
>>> Hello:
>>> 
>>> I have an HP DD3 Autoloader. It loads six tapes at a time.
>>> 
>>> Within Retrospect, I defined three storage sets (call them Moe,
>>> Larry, and Curly). I rotate them each week. At the start, I took 18
>>> blank tapes and labled them Moe1, Moe2,..., Larry1, Larry2, etc.
>>> 
>>> After several weeks, I got a message that it could not find Larry-6.
>>> Yet, the tape that I labeled Larry6 was in the drive.
>>> 
>>> When I asked Retrospect what it thought was in each slot of the
>>> autoloader (Configure>Devices), it said:
>>> 
>>> Slot 1: Larry-3
>>> Slot 2: Larry-2
>>> Slot 3: Larry-1
>>> Slot 4: Moe-4
>>> Slot 5: Larry-5
>>> Slot 6: Moe-1
>>> 
>>> It should look like:
>>> 
>>> Slot 1: Larry-1
>>> Slot 2: Larry-2
>>> Slot 3: Larry-3
>>> Slot 4: Larry-4
>>> Slot 5: Larry-5
>>> Slot 6: Larry-6
>>> 
>>> 
>>> Remember, these were blank tapes at the beginning of the week.
>>> 
>>> Any ideas?



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