When resources on a prepaid offering are activated, they must have enough capacity tokens to allow the activation for an entire billing window, which is 24 hours. The resources remain active until you deactivate them or until one resource uses all of its capacity tokens. Then, all activated resources from the record are deactivated. 

A postpaid On/Off CoD offering record contains resource descriptions, MSUs, speciality engines, and can contain capacity tokens that denote MSU-days and speciality engine-days. 

When resources in a postpaid offering record without  capacity tokens are activated, those resources remain active until they are deactivated, or until the offering record expires. The record often expires 180 days after its installation. 

When resources in a postpaid offering record with  capacity tokens are activated, those resources must include enough capacity tokens to allow the activation for an entire billing window (24 hours). The resources remain active until they are deactivated, until all of the resource tokens are used, or until the record expires. The record usually expires 180 days after its installation. If one capacity token type is used, resources from the entire record are deactivated. 

For example, for a z15 server with capacity identifier 502 (two CPs), a capacity upgrade through On/Off CoD can be delivered in the following ways: 

GLYPH<SM590000> Add CPs of the same capacity setting. With this option, the model capacity identifier can be changed to a 503, which adds another CP to make it a three-way CP. It can also be changed to a 504, which adds two CPs, making it a four-way CP. 

GLYPH<SM590000> Change to a different capacity level of the current CPs and change the model capacity identifier to a 602 or 702. The capacity level of the CPs is increased, but no other CPs are added. The 502 also can be temporarily upgraded to a 603, which increases the capacity level and adds another processor. The capacity setting 434 does not have an upgrade path through On/Off CoD because you cannot reduce the number of CPs and a 534 is more than twice the capacity. 

Use the Large System Performance Reference (LSPR) information to evaluate the capacity requirements according to your workload type. For more information about LSPR data for current IBM processors, see the Large Systems Performance Reference for IBM Z page of the IBM Systems website. 

The On/Off CoD hardware capacity is charged on a 24-hour basis. A grace period is granted at the end of the On/Off CoD day. This grace period allows up to an hour after the 24-hour billing period to change the On/Off CoD configuration for the next 24-hour billing period or deactivate the current On/Off CoD configuration. The times when the capacity is activated and deactivated are maintained in the z15 server and sent back to the support systems. 

If On/Off capacity is active, On/Off capacity can be added without having to return the system to its original capacity. If the capacity is increased multiple times within a 24-hour period, the charges apply to the highest amount of capacity active in that period. 

If more capacity is added from an active record that contains capacity tokens, the systems checks whether the resource has enough capacity to be active for an entire billing window (24 hours). If that criteria is not met, no extra resources are activated from the record. 

If necessary, more LPARs can be activated concurrently to use the newly added processor resources. 

