IBM 990 - Manual (Page 221)

Chapter 8. Capacity upgrades 209
CBU testing
Testing of disaster/recovery plans is easy with CBU. Testing can be accomplished by
ordering a diskette, calling the support center, or using the fast activation icon on the HMC.
Capacity BackUp operation example
Figure 8-10 shows an example of a 2084-B16 software model 304 to a 2084-B16 software
model 312 Capacity BackUp operation.
Figure 8-10 Capacity BackUp operation example
The PUs associated with Capacity BackUp are reserved for future use with CBU features (FC
7800) installed on the backup server. In this example, there should be eight CBU features
installed on the backup server 2084-B16 software model 304. When the production server
2084-B16 software model 312 has an unplanned outage, the backup server can be
temporarily upgraded to the target model planned, 2084-B16 software model 312, to get the
capacity to take over the workload on the failed production server.
Furthermore, customers can configure systems to back each other up. For example, if a
customer uses two 2084-A08 software model 303s for the production environment, both can
have three CBU features installed (or even more). If one server has a disaster, the other one
can be upgraded up to the approximately total original CP capacity.
Automatic CBU enablement for GDPS
The intent of the GDPS CBU is to enable automatic management of the reserved PUs
provided by the CBU feature in the event of a server failure and/or a site failure. Upon
detection of a site failure or planned disaster test, GDPS will concurrently add CPs to the
servers in the take-over site to restore processing power for mission-critical production
workloads. GDPS automation will:
Perform the analysis required to determine the scope of the failure; this minimizes
operator intervention and the potential for errors.
Automate authentication and activation of the reserved CPs.
Automatically restart the critical applications after reserved CP activation.
Control
Unit
Control
Unit
Control
Unit
Control
Unit
Control
Unit
ESCD ESCD
Current Model:
2084-B16
Model 304
with eight CBU features
(FC 7800)
Target Model:
2084-B16
Model 312
CBU Activation
Workload
Transfer
Production
Server
2084-B16
Model 304
Eight CBUs
Backup
Server
2084-B16
Model 312
2084-B16
Model 312
Cap
a
c
it
y
+ 8 CPs
Unplanned
Outage