Spanning LTO archive-sets between LTO4 & LTO5 tapes?

[Mel Matsuoka]

I know this is dumb question, but is it kosher to span a multi-tape LTO archive set across two different flavors of LTO tape media?

In other words, can I use 1x LTO-5 tape and 1x LTO-4 tape to archive a full 2 TB harddrive? It would be nice if I could use my cheaper LTO-4 tape stock to complete the spanned archive, instead of wasting a second LTO-5 tape just for the extra 500GB of archive data.

Since this is purely for archival purposes, I'm really not concerned about not being able to append to the LTO-4 tape later down the road, when LTO-6 drives become available.

I'm using BRU PE with HP Ultrium5 and Quantum Ultrium4 cartridges.

 

[Brian F Kobylarz]

First thoughts that come to mind:
Are you filling up that 2TB drive past 75% capacity before backing up?

Is all the data on that drive specific to a single project?

Consider archiving via subject matter or client or project etc. versus a "time machine" type of backup (other than system drive).
For example, several years downstream, it may be easier to find all "Kona scenics" when you have all the content stored on 3 tapes versus scattered among 12.

If you are archiving the total 2TB contents as a snapshot in time, can you split the data into two categories so that the two tapes stand individually versus spanning?
That reduces the risk of one tape failure or loss impacting the other.

For critical footage, consider a WORM tape that is kept in a separate, secure location.

As far as the different media / LTO flavor - it is just data, but it makes sense to use the manufacturers recommendations. In case of a problem, it eliminates one "cause" at the top of the list when engaging tech support.

As far as using both LTO 4 & 5 in the same backup - never tried - anyone else?

 

[Mel Matsuoka]

I already have an archival system that works well for my existing workflow. I work mainly in advertising/commercial work, so the scenario you describe isn't particularly practical for my needs.

The LTO tapes are just a redundant, off-site backup of my near-line "bare drive" archive drives, which is what I pull off the shelf and use when I need to load in archived projects for revisions and whatnot.

I'm just looking for a straightforward answer regarding the safety of mixed-format archive spanning. Thanks in advance.

 

[D Fuller]

I'm using BRU PE with HP Ultrium5 and Quantum Ultrium4 cartridges.

PM Tim Jones and ask about BRU specifically. He is a user of this board.