System checkout

Each resource in the system that has not been deleted from the resource selection list is tested during system checkout. System Checkout selection is accomplished by selecting All Resources from the Resource Selection Menu. User interaction is not allowed unless a problem has been detected and a question needs to be asked to isolate the problem.

Configuration processing for system checkout is different from that for option checkout, which impacts the effectiveness of the FRU Callout. Option checkout is the specification of an individual resource to test. When option checkout is chosen, the option chosen is tested first, and if a problem is found, it is traced back through its siblings and parents until it has been isolated. The configuration is processed from the outside in. When system checkout is chosen, the configuration is processed from the inside out. For example, the configuration is processed starting with the system planar, and works its way out on a per-card basis. First a card is tested, then the devices attached to the card are tested, and then the devices attached to the device attached to the card are tested, and so on. This process is repeated for each card attached to the system planar.

Option Checkout is more effective because the children are tested before the parent, which allows the parent to determine its own culpability above and beyond its own test results. The parent can implicate itself for no other reason than that its children are failing.