HP 12000 HP StorageWorks 12000 Gateway Virtual Library System User Guide (AH81 - Page 252

RAID1-level data storage RAID5-level data storage RAID6-level data storage redundancy replication on multiple disks, I/O operations can overlap in a balanced way, improving performance. A RAID that consists of at least two drives that use mirroring (100 percent duplication of the storage of data). There is no striping. Read performance is improved since either disk can be read at the same time. Write performance is the same as for single disk storage. A RAID that provides data striping at the byte level and also stripe error correction information. RAID5 configurations can tolerate one drive failure. Even with a failed drive, the data in a RAID5 volume can still be accessed normally. A RAID that provides data striping at the byte level and also stripe error correction information. RAID6 configurations can tolerate two drive failures. Even with two failed drives, the data in a RAID6 volume can still be accessed normally. RAID6 read performance is similar to RAID5, since all drives can service read operations, but the write performance is lower than that of RAID5 because the parity data must be updated on multiple drives. In a redundant system, if you lose part of the system, it can continue to operate. For example, if you have two power supplies with one that takes over if the other one dies, that's redundancy. The process of writing data to virtual tape, and after the backups are complete, writing the data to another virtual tape, known as the replication target, over the LAN/WAN. Similar to automigration. secondary node SSL certificate SATA SCSI SNMP A computer (node) that provides secondary administrating and control for backup and restore operations on a server cluster, and provides additional storage and multi-pathing capabilities on the system. Secure Sockets Layer certificate. A protocol designed to enable applications to transmit information back and forth securely. Applications that use this protocol inherently know how to give and receive encryption keys with other applications, as well as how to encrypt and decrypt data sent between the two. Some applications that are configured to run SSL include web browsers like Internet Explorer and Netscape, mail programs like GroupWise, Outlook, and Outlook Express, FTP (file transfer protocol) programs, etc. These programs are automatically able to receive SSL connections. To send an SSL connection, however, or to open a secure connection, your application must first have an encryption key assigned to it by a Certification Authority. Once it has a unique key of its own, you can establish a secure connection with every other application that can "speak" the SSL protocol. Serial Advanced Technology Attachment. Small Computer Systems Interface. A standard, intelligent parallel interface for attaching peripheral devices to computers, based on a device-independent protocol. Simple Network Management Protocol. A widely used network monitoring and control protocol. Data is passed from SNMP agents, which are hardware and/or software processes reporting activity in each network device (hub, router, bridge, and so on) to the workstation console used to oversee the network. The agents return information contained in a MIB (Management Information Base), which is a data structure that defines what is obtainable from the device and what can be controlled (turned off, on, and so on). 252 Glossary