6947ch08.fm Draft Document for Review April 7, 2004 6:15 pm
188 IBM eServer zSeries 990 Technical Guide
On/Off CoD can concurrently add processors (CPs, IFLs, ICFs, and zAAPs) up to the limit of
the installed book(s) of an existing server, and is restricted to the double of the current
installed capacity. On/Off CoD uses the CIU ordering process, initiated by the customer via
the Web using IBM Resource Link, and makes use of CUoD techniques. On/Off CoD requires
a special contract.

Unplanned upgrades

Unplanned upgrades can be done by the Capacity BackUp (CBU) for emergency or
disaster/recovery situations.
CBU is a concurrent and temporary activation of Central Processors (CPs) in the face of a
loss of customer processing capacity due to an emergency in any customer’s zSeries or
S/390 server or servers at any sites or locations. CBU cannot be used for peak load
management of customer workload. A CBU activation can last up to 90 days when a
disaster/recovery situation occurs.
CBU features, one for each “standby” CP, are optional on z990 servers and require spare PUs
on installed book(s) of the existing server. A CBU contract must be in place before the special
code that enables this capability can be loaded on the customer server.

Capacity upgrade functions

Table8-1 summarizes the capacity upgrade functions available for z990 servers.
Table 8-1 Capacity upgrade functions summary
8.2 Capacity Upgrade on Demand (CUoD)
Capacity Upgrade on Demand (CUoD) is a function available on z990 servers that enables

concurrent and permanent capacity growth.

The CUoD function is based on the Configuration Reporting Architecture, which provides
detailed information on system-wide changes, such as the number of configured processor
units, system serial numbers, and other information.
Function Upgrades Via Type Process
CUoD CPs, IFLs, ICFs,
zAAPs
Memory
I/O
LIC
or
hardware installation
Concurrent and
permanent Ordered as an normal
upgrade and activated
by IBM
CIU CPs, IFLs, ICFs,
zAAPs
Memory
LIC-only
cannot add book Concurrent and
permanent Initiated via Web and
activated by customer
On/Off
CoD CPs, IFLs, ICFs,
zAAPs LIC-only
cannot add book Concurrent and
temporary
(no time limit)
Initiated via Web and
activated by customer
CBU CPs LIC-only
cannot add book Concurrent and
temporary
(up to 90 days)
Ordered for
backup/recovery only
and activated by
customer