With Open System devices, you should consider the following as
you plan your PPRC implementation:
- Disk Considerations
- You must define at least one CKD device on the same cluster
of the subsystem where the Open System device resides. This CKD
device acts as an access device allowing you to issue the commands
that control PPRC on the fixed block (FB) device. This means that
if you want to manage both odd and even FB LSSs at least one odd and
one even CKD LSS is required.
- PPRC Path configuration
- There are two alternatives for configuring PPRC paths with Open
LUN management. It is possible to either share the physical links
between a CKD and an FB LSS or to use different physical links for
the different environments.
If there is a requirement to be able
to switch the Open LUN and System z® environments independently, then a different set of physical
links should be used for the two different sets of devices.
Note: This
is not necessary if it is possible for paths to be defined in both
directions on a single interface.
If the System z and Open LUN environments always
have their primary devices in the same site, then it is possible to
share the physical links, since there is no requirement to define
paths in different directions. However, in order to avoid possible
interference between the two environments you might choose to keep
the links separate.
- Determining which Open LUN volumes to designate for GDPS® PPRC management
- Different open systems platforms might have different requirements
for the volumes to be mirrored. These requirements do not change when
implementing GDPS with Open
LUN management. Consult the appropriate server and/or database platform
documentation. It is recommended however, that all production volumes
should be designated for PPRC use.
- GDPS Disk naming conventions
for Open LUN
- The Open LUN configuration requires that each ESS has a 4 character
name assigned to it. Consult the GDPS/PPRC INSTALLATION AND
CUSTOMIZATION GUIDE , ZG24–6703, for guidelines respecting
this naming convention.
See Peer-to-Peer Remote copy command descriptions to learn how to specify
Open System devices.