We are considering using the mainframe to create "ditto" copies of our 3590 AIX 
daily archive tapes for offsite storage. I handed a full ADSM tape plus a blank 
to one of our operators and requested a trial. He asked me if it was "the 
standard 3 file copy", to which I replied "Duh...I guess so.". (I'm known 
around the compute room for my incredibly quick, witty and intelligent 
responses. :-) He started the copy at around 2:45 p.m. and it hadn't finished 
by 5:00 p.m.. The "capacity bar" on the copy 3590 indicated about 75%. There 
were lots of tape starts and stops.

While the performance issue is something I'll need to discuss with a mainframe 
systems programmer, this did lead me to wonder how an ADSM 3590 tape volume is 
structured. I'm fairly certain that the tape volume header is separated from 
the archive data by a tape mark, but what does the rest of the tape look like? 

Thanks,

    Mark

Mark R. Rinfret, CBSI
mrinfret AT markrinfret DOT com (preferred)
mrinfret AT cbsinc DOT com
Pager: 401-925-7076
Phone: 401-222-1193 (Johnston Computer Room)