It can be a problem.  Most smaller shops are happy just getting an IBM VTS (or 
any VTS) and wouldn't consider the extra cost of the full VTS system with 
offsite capabilities.

In the newer VTS systems (TS whatever), there is an option, that is kind of 
neat.  You can export VTS tapes, the physical tape (which is made of multiple 
virtual tapes) to another VTS unit.  There is also a dual tape feature, in 
which certain virtual tapes, will be put on two physical tapes.  Well, for 
those tapes, create a small pool of physical tapes that are used for these 
copies.  Then export these copies (they are physically ejected from the VTS and 
can only be used by importing them into another VTS.  This is great if your 
disaster recovery plans also include a newer VTS.

But for the rest of us......

Produce physical tapes for offsite, by copying.  Hopefully, you are encrypting 
the tapes to be sent offsite.

Well, producing physical copies comes with its own set of problems.

Your VTS was defined with a virtual tape volume size of XX GB.  When the VTS 
virtual tape hits this size, and End of Volume signal is generated and an new 
virtual volume is obtained.

Copying these tapes can be expensive.  

Let's say that the virtual tape volume size is 2 GB.  You need at least a 3590 
tape (any size) to hold the data.  They are relatively cheap, when compare to a 
TS1120 tape (that has hardware encryption).  1:1 is easy at the disaster 
recovery site, but expensive to buy and a real pain to produce these tapes.  
(Operator mounts and tracking all these tapes)

I stack the tapes.  You can get a lot of virtual tapes on a physical tape.  

For most, but not all tapes  (I'll get to that later)....

I have another Dynam catalog DSN name, starting with a "V" (for vault), that is 
file X on a tape.  Then I just do a TDYNCOPY of the tape DSN from the VTS to 
the physical tape.  And I just run along with that process.  Note that a DSN 
that was a multi volume DSN of 2 GB volumes, will be combined by TDYNCOPY to a 
signal volume.  In most cases, this is ok.

For some DSNs, you can't combine volumes that way.

For example VMBACKUP, senses EOV and puts trailing information at the end of 
the tape, which includes the volser of the next tape that will be used.  It 
also puts information at the front of each tape, of the volser of the previous 
tape, and some info on what should be on this tape.  Any backup product that, 
for restores, allow you to bypass the first xx tapes, have something like that 
encoded.  For these tapes, you have to do a physical tape copy (like DITTO), 
recording the internal VOLSER.  

Now, do you create physical tapes for each of these?  Or do you still stack 
them, and unstack them if and when a disaster recovery is needed?  Do you buy 
some older 3590 drives so you don't waste your expensive TS1120 tapes?  

However, recently I've been playing around with another option.  External dasd.

Once you get a VSE system up (via tape), you have VSE Virtual Tape available.  
You can use that with the IP flavor (instead of the VSAM flavor) to store VSE 
Virtual Tapes.  Now, you can get a TB USB drive for around $1,500 and they are 
portable.  How about buying 3, (Grandfather, father, son), and copy the offsite 
data tapes, this way?  I'm still concerned about IP performance.  Another 
variant is to use a laptop with the extra hard drive.  Use the extra hard drive 
as your VSE Virtual Tape storage area, and send the extra drive off site.  In 
both cases, encryption is also a transparent option.

These options might not work well in the larger shops, but they can afford the 
hardware for proper duplication.  But for us smaller shops.....(I'm in the 2 TB 
size now)

(Sorry Hans, I didn't get out of meetings until lunch time, so no 10:30 call 
today.)

Tom Duerbusch
THD Consulting


>>> Hans Rempel <[email protected]> 6/3/2009 9:38 AM >>>
I have been reviewing entries in both lists and it appears that VM and VSE
neither have a easy way of move virtual tape volumes from the VTS to and
external tape media for offsite storage. I have been told that  MVS has a
facility (copy extract) to do this. For VSE I guess we could use Ditto  tape
copy to move virtual tapes to real one would be an option. One would need to
write a rexx program to read a tape catalog/tape report and build the job to
stack the tapes on one real tape. Is this the only option in VSE. Is there
anything  in VM. 

 

I guess I also find it hard to believe that the VTS itself has no internal/
backend process to do this.

 

I have dual posted this query

 

Thanks for your comments

 

Hans 

 

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