Filter
Top Products
procedure in order to apply jobset maintenance concurrently with maintenance
to VSE production.
32.6.2.2 Final Program Conversion
There are two key tasks associated with the translation and compilation of all the
VSE source materials for the final program conversion. First is the final mass
translation with the objective to translate all of the source modules in their
current state, overnight, automatically, and without errors. Second is the mass
compilation for the final conversion. The objective of this task is to compile and
link-edit all of the translated source modules overnight, automatically, and
without errors.
32.6.3 Switchover
The switchover weekend may not be a typical weekend, because it is a period
when operations are interrupted for the switchover. This interruption may be for
as little as a few hours or for as much as one or two days. Before switchover,
the production workload runs under VSE. After switchover, the production
workload runs under MVS.
The objective here is to switch VSE production over to MVS and continue
operations under MVS.
This transfer must be:
•
sufficiently fast to allow mass switchover to take place within the allotted
time
•
in conformity with the generated MVS JCL to avoid modification during the
initial runs
•
complete, because you should avoid coexistence of VSE and MVS systems.
In addition, backup operations on the VSE side are necessary before file transfer
to provide for a possible return to VSE in an emergency or for a recovery of
overlooked files. Backup operations on the MVS side are necessary to permit
recovery, if required, during initial MVS operations.
Switchover weekend activities include terminating VSE operations, backing up
the VSE and OS/390 environments, switching the network, executing file
migration and cataloging procedures, starting OS/390 operations with CICS
transactions and jobs according to normal weekend schedule, and supporting
OS/390 operations through review and resolution of exceptions. On Sunday, the
switchover is validated (stay under OS/390) or VSE fall back procedures are
implemented (return to VSE in case of unexpected difficulties).
32.6.3.1 Data/File Migration
On switchover day you have to have all of your data available to your new
system. This process of multiple dress rehearsals of switchover gives the whole
team confidence about the final switchover. At that time the team has been
through it many times.
Chapter 32. Conversion Process 517