IBM OS/390 User Manual

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A conversion team is normally chosen that will be dedicated to the project
until its end. Included with this team will be (perhaps) two application
programmers. Naturally, the number varies with the size and complexity of
the project. The team is responsible for converting all VSE applications. (As
previously mentioned a program conversion aid is normally used with this
approach.) Application programmers, not part of the project team, are not
disrupted during conversion work. They can continue to perform VSE
application development and maintenance activities.
The migration project has a visible end.
Because the project is an important one (obviously it wouldn
t have been
undertaken otherwise), and since no applications are cutover until all
applications are ready, the conversion effort will not lose steam. Priorities
will remain very high to complete application conversions, and to implement
OS/390 as the production system. Typically, the duration of realizing total
OS/390 production with this type of approach, is significantly less, (even up
to 50 percent less in duration), then with the kernel approach.
Staff is better prepared, trained, and experienced with OS/390 prior to
production operations.
OS/390 skills are developed during all conversion activities; that is,
conversion activities are performed on the OS/390 system. All learning and
hands-on activities are accomplished on a non-production OS/390 system,
thereby lessening future production exposures. Since there is no dual
operations of both VSE and OS/390, operators don
t get confused as to which
system they
re operating on.
2.5.3 VM/ESA Guest Support in Your VSE to OS/390 Migration
VM/ESA
s Guest Support has long been an important part of many VSE and
MVS(OS/390) customers operating environments. As you approach migrating
VSE to OS/390 you should consider the important roll VM/ESA plays in making
the job easier and more cost effective current and long term.
If you already have VM/ESA and you use VM/ESA
s Guest Support for running
your VSE system(s) then you already know the value VM/ESA delivers in this
environment. In migrating VSE to OS/390, VM/ESA continues to play an important
roll delivering as much or more value to your new OS/390 environment. If you
are not familiar with VM/ESA a more complete description of how to implement
multiple VSE and OS/390 images can be found in chapter 26 of this publication.
Chapter 26 also discusses the benefits and consequences of using VM/ESA and
LPAR to support multiple images both during and after the migration. For more
information on VM/ESA obtain a copy of 
VM/ESA V2R2.0 General Information,
GC24-5745 and 
VM/ESA V2R1.0 Running Guest Operations, SC24-5755.
2.5.4 Staffing Strategies
2.5.4.1 In-House Staff
There are two main strategies involved when deciding how to staff the migration
project. These typically are using existing in-house staff or hiring outside
consultants. Some considerations when using in-house staff are:
Chapter 2. Sizing the Effort
29