Backend tape usually refers to the tape drives that are assigned and dedicated 
to a tape based VTS system.  So those tape drives that are dedicated to the 
VTS, can't be touched by any other method.  They are not attached to the 
mainframe, but attached to the VTS.

So, if you are going to create disaster recovery tapes, there needs to be, 
somewhere, mainframe attached tape drives.  Then you just do a tape (virtual 
tape) to tape (real tape) copy.

We are going to be doing the same thing, but only with the older IBM 3494 B10.  
We had to buy 4 tape drives for the B10, and then we bought another two drives 
(IBM TS1120) for offsite backups with encryption.  We backup to the VTS, and 
when it is time to create off site tapes, tape to tape copies and stack a whole 
lot of files on a TS1120 cart <G>.  We didn't need the capacity of the TS1120, 
but the encryption was a big selling point.

I don't have a tape manager on VM.  So I plan on defining a range of volsers 
that are not in our DYNAM/T catalog for use by VM.  We can mount tape VM0001 
which will always be the current DDR copy of 520RES.  VM0002 is always the 
current copy of 520W01, etc.  Then, when it is time to create the off site 
backups, have VSE mount VM0001 and copy to a TS1120 scratch tape as file 1.  
Copy VM0002 to the same tape as file 2, etc.

I'm not sure if I will put the standalone utilities as file 1 or keep it on a 
separate tape(s).

Once all of this is defined, I'll bring up another LPAR and do a trial disaster 
recovery restore...

Tom Duerbusch
THD Consulting

Law of Cat Obstruction

  A cat must lay on the floor in such a position to obstruct the
  maximum amount of human foot traffic.



>>> "Smith, Ann (ISD, IT)" <[EMAIL PROTECTED]> 3/24/2008 4:55 PM >>>
It's probably me that is confused.
I have been told VM will have virtual tape but no native tape.
They also have used the term 'backend tape'.
I obviously have more to learn.

-----Original Message-----
From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On
Behalf Of Tom Duerbusch
Sent: Monday, March 24, 2008 3:14 PM
To: [email protected] 
Subject: Re: Question about virtual tape in a zVM environment

Someone there may be getting confused.

The IBM DS8300 is a virtual tape system.  It can work standalone as a
disk based VTS or, in conjunction with the robotics side to make it a
tape based VTS system (with a very large disk cache).

Then, there is the IBM TS1120.  These are real tape drives (not
virtual).

So, if your VM system can get access to your IBM TS1120 drives, just
backup to them for off site storage.
If you can only get access to the virtual tapes, then backup to a
virtual tape and, on a system that has access to the IBM TS1120, do a
tape copy from the virtual tape located in the IBM DS8300 to a real tape
mounted in the IBM TS1120.

The IBM TS1120 drives support hardware encryption.  That is great.
However, in a disaster recovery situation, it may not be so great.
Until you get the disaster recovery tested with encryption, you may want
to create your VM recovery tapes, without encryption enabled.

With the VTS, you do have to execute some code to tell the VTS what tape
you want.  VMTAPE should be able to handle this.

Tom Duerbusch
THD Consulting

Law of Cat Obstruction

  A cat must lay on the floor in such a position to obstruct the
  maximum amount of human foot traffic.

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