This sounds similar to what we are going to have to deal with when we
switch from 9940A drives to 9940B drives.  Here is what we are thinking
of doing.

The 9940A and 9940B drives use identical media.  The "B" drives can read
tapes written by "A" drives but cannot append to tapes written by "A"
drives.  The "B" drives can also rewrite a tape (starting at BOT) that
was previously written by "A" drives.

The 9940A drives and media are configured as HCART type.  We intend to
configure the 9940B drives as HCART also.  This will allow NBU to mount
the tapes in the "B" drives.  All tapes written by the "A" drives that
have valid, unexpired images will be suspended so that NBU will not try
to mount them for a backup.  This will, however allow the tapes to be
mounted for restores.  Any tape that is not suspended is usable for
backups.

Now, this will work for us as we are going to replace all the 9940A
drives at once, so there will not be a mixture of 9940A and 9940B
drives.  If you are going to have a mixture of LTO and LTO2 drives, this
probably won't work.  StorageTek was gracious enough to loan us a couple
of 9940B tape drives so we can test this out as a proof of concept.

This is all with NBU 3.4

On Fri, 2003-07-25 at 04:39, Larry Kingery wrote:
> > I have a question regarding configuration which would allow to use
> > LTO media in LTO2 drive. I have two LTO2 drives in STK 180 library
> > configured on NetBackup Server as HCART2 drives. Appropriate storage
> > unit is created, again, as a HCART2 storage unit. Originally, we
> > created barcode rules which would allow as to import new, LTO2 media
> > as HCART2 and old LTO media as HCART. Of course storage unit refused
> > to accept HCART media for a backup.  Step two was to create second
> > storage unit as HCART pointing to the same library and drives, and
> > direct backups into that unit. Backup failed with error 219, storage
> > unit is not available, however both drives were available for use. I
> 
> The drives themselves also have a type, which needs to match what's
> in the storage unit.  You've created a storage unit basically saying
> it could use any HCART drive it found in the robot, but there aren't
> any.  
> 
> > guess my question is if somebody has an experience in configuring
> > NetBackup to accept lower density media in higher density drives and
> > how it was done. Another thing I would like to try is to import LTO
> > (HCART) media as HCART2 media, changing our barcode rule.  But I am
> > concern that NetBackup would utilize it appropriate and write/read
> > from tape without errors.
> 
> If you can use the tapes in the drives, NBU can also.  I am not sure
> if there are different media for LTO and LTO2, and if so if they are
> backward compatible.  If they are compatible, and you have only one
> type of drive, then change the type of the media to all match the
> drive type.
> 
> The reason there's HCART and HCART2, etc, is to keep different drive
> types from trying to mount "foreign" tapes, or to keep tapes written
> by a newer drive from being mounted in an older version (which would
> presumedly not be able to read them and therefore consider them blank
> tapes).  
> 
> > 
> > Backup environment is NetBackup 4.5 (no patches) on Windows 2000
> > server and L180 with LTO Gen2 fibre drives.
> > 
-- 
Jack L. Forester, Jr.
Sr. UNIX Systems Administrator
Lockheed Martin Information Technology
(304) 625-3946