LTO3 or LTO4

Hi JM,

From past experiences I would have to say that the LTO3 tapes could be read in the LTO4, but not the reverse.

It's not just the density of the media, but the format used by the drive itself that gives the capacity.

So the short answer would be, no, the LTO3 would not be able use the higher capacity media. The LTO4 drive, on the other hand, could be used to perform restores from the LTO3 media.

I hope this helps,
Luc.

You can't use LTO3 drive to read LTO4 tapes.
You can use LTO4 drive to read and write LTO3 media as well as LTO4 media.

Of course LTO3 medias written by LTO4 drive can be read using LTO3 drive

Here is a table from IBM Redbook "IBM System Storage Tape Library Guide for Open Systems"

IBM Ultrium Tape Drive	IBM TotalStorage LTO Ultrium Data Cartridge
	800 GB (Ultrium 4)	400 GB (Ultrium 3)	200 GB (Ultrium 2)	100 GB (Ultrium 1)
Ultrium 4	Read/Write	Read/Write	Read only	N/A
Ultrium 3	N/A	Read/Write	Read/Write	Read only
Ultrium 2	N/A	N/A	Read/Write	Read/Write
Ultrium 1	N/A	N/A	N/A	Read/Write

drives can read 2 generations back & write one generation back.

 Thanks guys for the posts!  Not the answer that I was hoping for but you did answer my questions.  Thanks again for the help.