DLT 7000 dirves in STK 9714 going down

I am having a problem with DLT 7000 drives going down in our
Storagetek 9714 robotic drive cabinet. We are running Veritas
Netbackup 3.4.1 on a Solaris 2.6 server. Everything runs fine dirring
the week while ecrementals are running but the weekends are a
nightmare. Every monday morning at least one drive is down (2 drives
this morning) and backup windows have been missed as a result. Were
are the log files located that would show the drive errors. It is my
understanding that drives will automatically down themselves after 5
errors in a 24 hour period. I have had techs come out and replace the
drives multiple times, replace SCSI connections and verify everthing
is working. I need to know when the drives are going down and try to
determine what tape is installed and I am going to start a process of
replacing tapes. Any help in this is appreciated.

Thanks,

Down and frustrated

On Mon, 22 Sep 2003 05:39:28 -0700, sedwards wrote:

I am having a problem with DLT 7000 drives going down

You probably don't have enough information going to your tape drives.
You need to keep in mind that tape drives require a constant stream of
data. Therefore if you have machines or networks that aren't capable of
keeping up with the tape drive speed, the tape drives themselves will stop
and start when there is not enough data to fill the pipe, in your case you
must have 5MBps/tape drive. I have seen this be the root cause of tape
drives failing during a backup. IIRC the 9714 is capable of handling 6
drives thus you _must_ have 30MBps going to your library. The first thing
you should try is turning off half of your tape drives. Then you might
want to consider putting MRTG infront on your network to monitor bandwidth
to make sure you are filling the bandwidth required by the number of tape
drives you are running. I hope this helps in your diagnosis.

Regards,
Jake