This publication is for system programmers
who run OS, DOS, DOS/VS, DOS/VSE, OS/VS1, OS/VS2 SVS, OS/VS2 MVS, and VM/370 under
the VM/370 control program. It is also for VM/370 system programmers who plan to use
these system/360 or System/370 operating
systems under the control of VM/370. Users of the control program (CP) should
refer to the Virtual Machine Order No. GC20-1820, and Faci1ity/37Q: Order No. GC20-1806. Users of the conversational monitor
system (CMS) should refer to the Facility/370: £MS Order No. GC20-1819. Users of
communications
refer to the Commun icat ions the remote
subsystem (RSCS) Virtual .Remote (RSCS) GC20-1816.
spooling
should Machine U Users of the interactive problem control
system (IPCS) should refer to the IBH Faci1illLllQ: £Q!li£Q1 (IPCS) User's Guide, Order No. GC20-1823. OR G AN I Z A T ION This publication contains these sections: • "Section 1. General Considerations"
provides both introductory and general
usage information. The introductory
information briefly describes the
features of VM/370 as.they apply both to
the virtual machine and to the operating
system that is running in it. The
general usage information discusses
those aspects of running systems under VM/370 that are common to
all systems. It also describes how to
use VM/370 functions more efficiently
when running operating systems under VM/370. • "Section 2. VM/370 in a Virtual Machine"
explains how to test and update a VM/370 system that is itself operating under VM/370. • "Section 3. DOS/VS in a Virtual Machine" provides operating specific
to running DOS, DOS/VS, and DOS/VSE in a
April 1, 1981
Preface
virtual machine. It contains system
planning considerations for generating
and using these systems under VM/370, rather than stand-alone. • "Section 4. OS/VS in a Virtual Machine" provides operating information specific
to running OS, OS/VS1, and OS/VS2 in a
virtual machine. It contains system
planning considerations for generating
and using these systems under VM/370, rather than stand-alone.
TER MINOLOGY In this publication,
terminology is used:
the following • 2305 refers to the IBM 2305 Fixed Head • • • • • storage, Models and 2. 3270 refers to a series of display
devices, namely, the IBM 3275, 3276,
3277, and 3278 Display Stations. A
specific device type is used only when a
distinction is required between device
types. 3330 refers to the IBM 3330 Disk Storage, Models 1, 2, and 11; the IBM 3333 Disk Storage and Control, Models 1
and 11; and the 3350 Direct Access Storage operating in 3330/3333 Model 1
or 3330/3333 Model 2 compatibility mode. 3340 refers to the IBM Disk Storage; Models A2, B1 and B2; and, the
3344 Direct Access storage, Model B2. 3350 refers to the IBM 3350 Direct
Access Storage, Models A2 and B2, in
native mode.
FB-512 refers to the IBM 3310 and 3370 Direct Access Storage Devices.
Any information about display terminal
usage also applies to the IBM 3138, 3148,
and 3158 Display Consoles when used in
display mode, unless otherwise noted.
Any information to the 3284 or 3286 printer also pertains to the
IBM 3287, 3288, and 3289 printers, unless
otherwise noted. Any information pertaining to the IBM 2741 terminal also applies to the IBM 3767
terminal, Model 1, operating as a 2741,
unless otherwise specified. Preface iii

Paqe of GC20-1821-3 As Updated April 1, 1981 by TNL GN25-0840 For a glossary of VM/370 terms, refer to Facility/370: GlossarI Order No. GC20-1813. PREREQUISITE PUBLICATIONS COREQUISITE PUBL ICATIONS The reader must also have a basic knowledge
of the operating systems he will be using under For the titles and abstracts
of the appropriate publications, refer to
the latest IBM Order No. GC20-0001. Guide, Order No. GC20-1807 GeneratiQn Order No. GC20-1801 Guide, Order No. GC20-1819 Command and Reference, Order
No. (;C20=1818- Terminal User's Order No. GC20-1810 ASSOCIATED PUBLICATIONS IBM Facility/370: ,Rg£ordiruz Guide, Order No. GC20-1809 Q2LY2, Environmental Printing Order No. GC28-0772 You are welcome to submit recommendations
and hints about generating and running
operating systems in a virtual machine for
possible inclusion in this publication. You can write a letter, or use either the
suggestion Input Form or the Reader's
Comment Form at the back of this
publication. Send your recommendations to:
IBM Corporation Programming Publications Dept. G60, P.O. Box 6
Endicott, New York 13760 It is understood that IBM and its
affiliated companies shall have the
nonexclusive right, at their discretion, to
use, copy, and distribute any or all
submitted information or material, in any
form, for any and all purposes, without any
obligation or commitment to the submitter,
and that the submitter has the right to
submit such information or material upon
such a basis.
When submitting recommendations, please
indicate the type of operating system (that
is, DOS/VS, vs 1) and the release level tha t
is used under VM/370. Suggestions for generating and running
operating systems can cover any topic
currently in the book or can address areas
that you think should be added to this
publication. Submit input in whatever
manner and format is most convenient, but
ensure that it is legible, understandable,
and follows these guidelines: • Do not include changes to object modules
since such modules are likely to change
over time. • Do not describe a problem unless you
have an appropriate solution,
circumvention, or alternative included.
Tips on things you have to watch out
for, or unusual circumstances that can
occur in virtual machine operation are,
however, suitable topics. • If you describe useful EXEC procedures
for CMS or other programs, test them out
to ensure that they work. The recommendations in the DOS/VS and OS/VS areas of this publication are meant
to help an installation in generating
operating systems to run more efficiently
under VM/370 and also contain operational
considerations or hints when using virtual
machines. Many of these recommendations
were suggested by VM/310 users and have not
been submitted to any formal IBM test. As
a result, potential users should evaluate
the applicability of the recommendations to
their installation before implementation.
iv IBM VM/370 Operating Systems a virtual Machine