202 IBM ^ zSeries 990 Technical Guide
Figure 8-8 CIU upgrade selection screen
An On/Off CoD upgrade for processors cannot be applied while a previous On/Off CoD or a
CBU is activated. In those cases, the requested upgrade can be retrieved, but can be applied
only after the current temporary upgrade is deactivated. On/Off CoD upgrades for memory
can be retrieved and applied, even while a CBU or a previous On/Off CoD activation is in
8.4 On/Off Capacity on Demand (On/Off CoD)
The On/Off Capacity on Demand (On/Off CoD) for z990 servers is the ability for the z990 user
temporarily turn on unowned PUs, unassigned CPs, and unassigned IFLs available within
the current model, to help meet customer’s peak workload requirements. On/Off CoD uses
the Customer Initiated Upgrade (CIU) process to request the upgrade via the Web, using IBM
Resource Link.
On/Off CoD requires the CIU Enablement feature (FC 9898) and the On/Off CoD Enablement
feature (FC 9896) installed.
The resources eligible for temporary use are CPs, ICFs, IFLs, and/or zAAPs. Temporary use
of memory and I/O ports is not supported. Spare PUs that are currently unassigned and
unowned can be temporarily and concurrently activated as CPs, ICFs, IFLs, or zAAPs via
LIC-CC, up to the double of the current installed capacity, and up to the limits of the physical
server size. This means that an On/Off CoD upgrade cannot change the z990
server model
(2084-xxx), as additional book installation is not supported. However, On/Off CoD may
change the server’s
software model (3xx) if additional CPs are requested.
Important: The On/Off CoD capability can coexist with Capacity BackUp (CBU)
enablement. Both On/Off CoD and CBU LIC-CC can be installed on a z990 server, but the
On/Off CoD activation and CBU activation are mutually exclusive.

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