IBM z/OS Automatic Enablement of CBU for Geographically Dispersed Parallel Sysplex (GDPS)

The z990 supports concurrent memory upgrade. This capa-

bility will allow a processor’s memory to be increased with-

out disrupting the processor operation. To take advantage

of this capability, a customer should not plan processor

storage on the 16 or 32 GB increments. A customer with a

Model A08, for example, with 24 GB of storage will be able

to concurrently upgrade to 32 GB but will not be able to get

to the next increment of 40 GB without a disruption.

Plan Ahead for PUs is done by ordering a “more book”

model. For example, if a customer needs 5 PUs initially,

but plans to grow to need 10 PUs, he should not order an

A08, but a Model B16 with only 5 PUs initially active.

The Plan Ahead process can easily identify the customer

conﬁ guration that is required to meet future needs. The

result of concurrent conditioning is a ﬂ exible IT infrastruc-

ture that can accommodate unpredictable growth in a low

risk, nondisruptive way. Depending on the required Con-

current Conditioning, there should be minimal cost associ-

ated with dormant z990 capacity. This creates an attractive

option for businesses to quickly respond to changing

environments, bringing new applications online or growing

existing applications without disrupting users.

z990 Server Capacity BackUp (CBU)

Capacity BackUp (CBU) is offered with the z990 servers

to provide reserved emergency backup CPU capacity for

situations where customers have lost capacity in another

part of their establishment and want to recover by adding

reserved capacity on a designated z990 server. A CBU

system normally operates with a “base” CP conﬁ guration

and with a preconﬁ gured number of additional Processor

Units (PUs) reserved for activation in case of an emergency.

The z990 technology is suited for providing capacity

backup. The reserved CBU processing units are on the

same technology building block, the MCM, as the regular

CPs. Therefore, a single server can support two diverse

conﬁ gurations with the same MCM. For CBU purposes, the

Models A08, B16, C24 & D32 can scale from a 1-way to a

32-way; with the purpose of providing capacity backup.

The “base” CBU conﬁ guration must have sufﬁ cient

memory and channels to accommodate the potential

needs of the larger CBU target machine. When capacity is

needed in an emergency, the primary operation performed

is activating the emergency CBU conﬁ guration with the

reserved PUs added into the conﬁ guration as CPs.

Customers who have an active Remote Support Facility

connection can perform a CBU upgrade automatically and

within a matter of minutes, right from their CBU machine’s

Hardware Management Console (HMC). For more informa-

tion on how a CBU upgrade can be activated automati-

cally, please refer to the z990 Capacity BackUp Users'

Guide found on IBM Resource Link.

The z990 supports concurrent CBU downgrade. This func-

tion enables a Capacity BackUp server to be returned to

its normal conﬁ guration without an outage (i.e. PowerOn

Reset).

Automatic Enablement of CBU for Geographically Dispersed Parallel Sysplex (GDPS)

The intent of GDPS support for CBU is to enable auto-

matic management of the reserved PUs provided by the

CBU feature in the event of a processor failure and/or a

site failure. Upon detection of a processor failure or site

failure, GDPS will activate CBU to dynamically add PUs to