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Draft Document for Review April 7, 2004 6:15 pm 6947ch08.fm
Chapter 8. Capacity upgrades
This chapter describes the zSeries 990 server’s capacity upgrade functions and features. It
also includes capacity measurements and performance considerations.
The z990 servers have the capability of concurrent upgrades, without a server outage, in both
planned and unplanned situations.
In most cases, a z990 capacity upgrade can also be nondisruptive, without a system outage.
The following sections are included:
򐂰“Concurrent upgrades” on page 186
򐂰“Capacity Upgrade on Demand (CUoD)” on page188
򐂰“Customer Initiated Upgrade (CIU)” on page 194
򐂰“On/Off Capacity on Demand (On/Off CoD)” on page 200
򐂰“Capacity BackUp (CBU)” on page 204
򐂰“Nondisruptive upgrades” on page208
򐂰“Capacity planning considerations” on page217
򐂰“Capacity measurements” on page222
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