HP ProLiant 4500 Compaq ProLiant Cluster HA/F100 and HA/F200 Administrator Gui - Page 171

Glossary Active/active Active/standby Arbitrated loop Array controller Availability Blink LEDs Business-critical Cluster A state in which each host bus adapter is processing data when the cluster is operating normally. A state in which one host bus adapter is processing data and the other is in a booted, but inactive, state when the cluster is operating normally. The standby node does not execute its own clustered applications and has no cluster groups to fail over to the active node. A connection method in which two or more ports can be interconnected, but only two ports at a time can communicate. A hardware device that facilitates communications between a host and one or more devices organized on an array. Also called RA4000 controller. A measure of how well a computer system can continuously deliver services to its clients. Availability is typically expressed as a percentage, with 100 percent being the best possible rating. The ability to light the drive tray LEDs on a particular RA4000. Applications that are key to business success but not significant enough to justify the high cost of a traditional clustering solution. Their failure causes lost revenue, decreased productivity, and customer dissatisfaction. A group of systems that work collectively as a single system to provide fast, uninterrupted computing service. Clustering is a way to increase availability, processing capacity, and I/O bandwidth.