As you plan your migration to a zEnterprise server, consider the
following:
- Relatively few migration actions are new when
coming from a z10™ EC or a z10 BC server. Migration to
a zEnterprise® server
has, as its base, a migration to the z10 EC
or z10 BC servers. This means
that if you are migrating to a zEnterprise server
from a z10 EC or z10 BC server, and have performed the migration actions
associated with the z10 EC or z10 BC, you have fewer migration
actions than if you were migrating from a server prior to the z10 EC or z10 BC and have not yet performed the migration actions
associated with these servers. There are, in fact, very few new migration
actions to perform on z/OS® for
a zEnterprise server
if you have already migrated to a z10 EC
or z10 BC server. It is important
to note that you can migrate directly to a zEnterprise server without installing the intermediate
servers, but you still need to ensure that any migration considerations
are satisfied for the servers that you "skipped." To read about z10 EC and z10 BC server migration actions, see Migrate to a System z10 server.
- Support is delivered by service (and FMID web
deliverables for ICSF). The delta (from a z10 EC or z10 BC)
support for a zEnterprise server, excluding cryptographic support,
is delivered by service (PTFs). The cryptographic support for the
zEnterprise server continues to be FMIDs, many of which are still
available in web deliverables. Different ICSF web deliverables, providing
different levels of support, are available for different releases
of z/OS. (See "Decide on the steps you will take for your migration
to a zEnterprise server" in Actions you can take before you order a z196 and z114 server for further
information.)
- Larger coupling facility structure sizes might
be necessary. When you change coupling facility control code
(CFCC) levels, your coupling facility structure sizes might change.
zEnterprise servers initially ship with CFCC level 17. If, as part
of your migration to a zEnterprise server, you change CFCC levels
(either by placing a coupling facility on the zEnterprise server or
by moving the coupling facility to a z10 EC
or z10 BC at a later CFCC level),
you might have larger structure sizes than you did previously. If
your CFCC levels are identical, structure sizes are not expected to
change when you migrate from a previous server to a newer generation
server.
- Use the same software level throughout a sysplex. Having
members of a sysplex at the same software level (other than during
brief migration periods) is good software management policy.
- Migrate hardware and software at different times. To
minimize the amount of change (and therefore risk) that you experience
at one time, do not migrate your software release level at the same
time that you migrate your hardware.
- Update SCRT to latest version. If you use
SCRT, make sure it is at the latest level. This is a requirement for
vWLC, as well as when you upgrade servers. The latest level of SCRT
can be downloaded from the SCRT web site at http://www.ibm.com/eserver/zseries/swprice/scrt/.