IBM z/OS - page 39

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.