Avago Technologies AcceleRAID 170LP - Manual (Page 76)

G-18 AcceleRAID 170LP Installation Guide
During the RAID set expansion process, which includes re-striping data
from the old (smaller) RAID set to the new (expanded) RAID set, the
controller continues to service host I/O requests.
MTBF
Mean Time Between Failures, the average time from start of use to failure in
a large population of identical systems, computers, or devices.
MTDL
Mean Time until Data Loss, the average time from startup until a component
failure causes a permanent loss of user data in a large population of disk
arrays.
Narrow SCSI
8-bit wide standard SCSI. Compare with Fast SCSI, Fast/Wide SCSI, Ultra
SCSI (Fast 20 SCSI), Ultra Wide SCSI, Ultra2 SCSI (Fast 40 SCSI),
Ultra160 SCSI (Ultra3 SCSI), and Wide SCSI.
NOS
Network Operating System, an operating system that has special features for
connecting computers and peripheral devices into a LAN.
NVRAM
Non-Volatile Random Access Memory, a memory unit equipped with a
battery so that the data stays intact even after the main power had been
switched off.
Offline
A Logical Drive is in an “offline” state if no data can be read from it or
written to it. Offline does not apply to physical disk drives. System
commands issued to offline logical drives are returned with an error status;
no operations can be performed on offline logical drives. See also Logical
Drive States, Critical State, and Online.