Understanding Online vs. Offline Activation Methods

Online Activation Mode

Online (dynamic) activation occurs when you activate processors, using the icod_modify command in either instant or deferred mode, while HP-UX is running. Online activation is the standard method used to activate processors.

Offline Activation Mode

Offline (manual) activation consists of deconfiguring processors that would otherwise be deactivated and available for online activation. Offline activation occurs when you activate processors using the following process:

A reboot is required for offline activation.

Most software applications work fine with the online activation method. However, some applications erroneously regard inactive processors to be active processors. These types of applications may exhibit functional or performance problems. Offline (manual) activation may be necessary for these types of applications.

You may want to test your application for proper operation in online activation mode. For information on testing your application, see “Processor Test Activation on iCOD Systems”.

If you are not satisfied with your application behavior in the (dynamic) online activation mode, you may want to switch the iCOD system to offline (manual) activation mode. For information on configuring your system in offline activation mode see Appendix A “Offline Configuration and Activation of Processors ”.

	NOTE: Booting a system to the HP-UX prompt can be time consuming, depending on your software and hardware configuration.

For information on how to dynamically activate processors, see “Increasing Processor Capacity”.

For information on how to manually configure processors, see Appendix A “Offline Configuration and Activation of Processors ”.

Advantages and Disadvantages of Online Activation

Advantages:

• no reboot required

• immediate additional processing power

• one simple command to activate

• automatic replacement of failed processors

Disadvantages:

• some applications may not take advantage of the additional processing power and experience functional or performance problems

• some applications may erroneously regard the inactive processors as active processors and experience licensing problems

Advantages and Disadvantages of Offline Activation

Advantages:

• applications should not experience functional or performance problems

• applications should not experience licensing problems

Disadvantages:

• requires a reboot to activate a processor

• complex, multi-step process

• no automatic replacement of failed processors

• the HP application, Predictive, reports the deconfigured processors

• L- and N-Class systems show system alerts for deconfigured processors