HP 3000 Manuals HP 3000 Manuals
GLOSSARY The following terms are specific to the SPU Switchover/XL product. Alternate System The SPU that a nonsystem volume set is mounted on if the home system fails, the home system is undergoing maintenance, or the home system requires a load balancing. CPU Central processing unit. FLEX The fiberlink exchange (FLEX) instruction set defines the commands that can be sent down to fiber link (FL) disk drives. Home System The SPU that a nonsystem volume set should mount on if there is a conflict between two SPUs attempting to mount the same volume set. Host-to-Host Host-to-host messages are FLEX messages that are sent between two SPUs. Host-to-Host DM The host-to-host device manager (DM) controls the sending and receiving of messages sent between two SPUs. This device manager sends messages to the HP-FL DAM. HP-FL HP fiber link. HP-FL DAM The HP fiber link device adapter manager controls the information sent over the fiber link cable. Connects to the fiber link disk controller. Nailed Terminal A terminal permanently assigned an ldev number in the NMMGR configuration file. All terminals that will be accessed programmatically (FOPENed) must be nailed. Nonnailed Terminal A terminal without a permanently assigned ldev number in the NMMGR configuration file. Ldev numbers are dynamically assigned to a terminal connection upon request from a pool of available ldev numbers assigned through the NMMGR configuration file. When the connection is ended, the assigned ldev number is returned and available for use by another connection. Nonsystem Volume Set A volume set that does not contain the system directories. OpenView DTC Manager A window environment containing a data terminal controller for management of the terminals connected to the system. SPU The system processing unit. SPU Switchover/XL The product that allows you to switch processing from one SPU to another so that processing of data on shared volume sets can continue. SPU Switchover/XL Configuration File A file that the user creates to define the relationships between the systems and volume sets in the switchover environment. Switchable Volume Sets The nonsystem volume sets that are connected to both systems by fiber link and are configured as switchable volume sets. Switchback The returning of switchable volume sets from the alternate system to the home system. Switchover The switching of switchable volume sets from the home system to the alternate system. System Status Message The message that is sent between two SPUs to monitor the system state of each other.