IBM z/OS - Manual (Page 39)

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On a z990, the scope of Channel Subsystem I/O Priority
Queuing is a Logical Channel SubSystem.
Channel Subsystem Priority Queuing complements the
IBM Enterprise Storage Server capability to manage I/O
priority across CECs.
With IRD, the combination of z/OS and zSeries working in
synergy extends the world-class workload management
tradition of S/390 and OS/390 to ensure that the most
important work on a server meets its goals, to increase the
effi ciency of existing hardware, and to reduce the amount
of intervention in a constantly changing environment.
Parallel Sysplex Professional Services
IBM provides extensive services to assist customers
with migrating their environments and applications to
benefi t from Parallel Sysplex clustering. A basic set of
IBM services is designed to help address planning and
early implementation requirements. These services can
help you reduce the time and costs of planning a Parallel
Sysplex environment and moving it into production. An
advanced optional package of services is also available
and includes data sharing application enablement, project
management and business consultation through advanced
capacity planning and application stress testing. For more
information on Parallel Sysplex Professional Services, visit
IBM’s Web site at ibm.com/servers/eserver/zseries/pso/
services.html.
Geographically Dispersed Parallel Sysplex
The GDPS solution, based on Peer-to-Peer Remote Copy
(PPRC), referred to as GDPS/PPRC, is designed with the
attributes of a continuously availability solution. PPRC is a
hardware solution that is designed to synchronously mirror
data residing on a set of disk volumes, called the primary
volumes in site 1, to secondary disk volumes on a second
system in site 2. Only when the primary storage subsystem
receives “write complete” from the secondary storage sub-
system is the application I/O signaled completed. GDPS/
PPRC complements a multisite Parallel Sysplex environ-
ment by providing a single, automated solution to dynami-
cally manage disk and tape storage subsystem mirroring,
processors, and network resources to allow a business
to attain “continuous availability” and near transparent
business continuity/disaster recovery without data loss.
GDPS/PPRC provides the ability to perform a controlled
site switch for both planned and unplanned site outages,
while maintaining full data integrity across multiple storage
subsystems. GDPS/PPRC is designed to be application
independent and therefore is expected to be able to cover
the customer’s complete application environment. GDPS
supports both the synchronous Peer-to-Peer Remote Copy
(PPRC) as well as the asynchronous Extended Remote
Copy (XRC) forms of remote copy. GDPS/PPRC is a con-
tinuous availability solution and near transparent business
continuity/disaster recovery solution that is designed to
allow a customer to meet a Recovery Time Objective
(RTO) of less than an hour, a Recovery Point Objective
(RPO) of no data loss, and protects against metropolitan
area disasters (up to 40 km between sites). GDPS/XRC is
a business continuity/disaster recovery solution that allows
a customer to meet a RTO of one to two hours, an RPO of
less than a minute, and helps protect against metropolitan
as well as regional disasters, since the distance between
sites is unlimited. XRC can use either common communi-
cation links and channel extender technology or dark fi ber
as the connectivity between sites.