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Glossary–20
HSG80 Array Controller V8.7 Command Line Interface Reference Guide
Glossary
PTL
Port-Target-LUN. The controller method of locating a device on the controller device bus.
public NL_Port
An NL_Port that attempts login with the fabric and can observe the rules of either public or
private loop behavior. A public NL_Port may communicate with both private and public
NL_Ports.
PVA module
Power Verification and Addressing module.
RAID
Redundant array of independent disks. Represents multiple levels of storage access developed
to improve performance or availability or both.
RAID level 0
A RAID storageset that stripes data across an array of disk drives. A single logical disk spans
multiple physical disks, allowing parallel data processing for increased I/O performance.
While the performance characteristics of RAID level 0 is excellent, this RAID level is the only
one that does not provide redundancy. Raid level 0 storagesets are referred to as stripesets.
RAID level 0+1
A RAID storageset that stripes data across an array of disks (RAID level 0) and mirrors the
striped data (RAID level 1) to provide high I/O performance and high availability. Raid level
0+1 storagesets are referred to as striped mirrorsets.
RAID level 1
A RAID storageset of two or more physical disks that maintains a complete and independent
copy of the entire virtual disk's data. This type of storageset has the advantage of being highly
reliable and extremely tolerant of device failure. Raid level 1 storagesets are referred to as
mirrorsets.
RAID level 3
A RAID storageset that transfers data parallel across the array’s disk drives a byte at a time,
causing individual blocks of data to be spread over several disks serving as one enormous
virtual disk. A separate redundant check disk for the entire array stores parity on a dedicated
disk drive within the storageset. See also RAID level 5.