The following reponse form Veritas deals with Solaris  servers,ours are
2.6.  Hope this helps.

It was noticed was the /Kernel/drv/st.conf
files are not configured on the master or media servers.  Without these
files configured properly the tape drives are writing in "Fixed Block" mode
rather than "Variable Block Length" as NetBackup requires.  Please see
pages
55 through 57 in the Media Manager Device Configuration Guide Version 3.4.
This can also prevent problems when it comes to restoring. After the
changes
are made, at your convenience, a reconfigure reboot (reboot -r) of the
system is required. We also suggest that you suspend currently ACTIVE or
FULL media, as listed in the "available_media" output, so not to mix modes.
It is explained below:

A reconfigure reboot (reboot -r) will be needed to make the change
effective.

You'll also need to 'suspend' any media written prior to the change by
doing
a

/usr/openv/netbackup/bin/admincmd/bpmedia -suspend -ev
which will prevent further writes to these tapes

If one of these suspended media is called for a file restore, create the
touch file /usr/openv/netbackup/db/config/FIXED_LENGTH_BLOCKS to read those
'old' media
in fixed blocks. Remove that file after the restore is done to write
backups
correctly.

Eventually those 'old' media will expire, their status will change from
"SUSPENDED" to "AVAILABLE" automatically and this step will no longer be
necessary.
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John P. Vrla                 Infrastructure Analyst
CETS/GIS/IFS            Unix-MidRange Computing Skill Center
214-951-4736              Dallas/Pegasus Place/B-7-W39
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