HP StorageWorks 8000, Руководство пользователя

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Glossary
256 HP StorageWorks NAS 8000 User’s Guide
NFS (Network File System)
An network protocol designed by Sun Microsystems that allows all network users to access shared
files stored on computers of different types. Users can manipulate shared files as if they were
stored locally on the user’s own hard disk.
With NFS, computers connected to a network operate as clients while accessing remote files, and
as servers while providing remote users access to local shared files. The NFS standards are
publicly available and widely used.
Package
See Failover Package.
Packet
A block of information sent across a network. Packets contain header (which handle addressing),
error correction, checksums, and data.
Permission
The ability of a particular user in a multi-user computer environment to access a particular
resource by means of a user account. Permissions are stored in the system, in a file called a
permissions log. Permissions are checked when a user attempts to access a resource.
Permission bits
Bits that identify the read/write/execute (rwx) privileges for a UNIX file’s owner, group, and
anyone else that needs access to the file (other).
Physical drive
A term for the hard drives installed in the NAS server. The NAS server can contain up to 12
physical drives.
Primary Domain Controller (PDC)
A domain controller that has been assigned as or has negotiated to become the primary
authentication server for the domain of which it is a part.
RAID (Redundant Array of Independent Disks)
A disk array in which part of the physical storage capacity is used to store redundant information
about user data stored on the remainder of the storage capacity. The redundant information enables
regeneration of user data in the event that one of the array’s member disks or the access path to it
fails.
Redundancy group
Group of physical disks that contain redundant data, as defined by the RAID level assigned to the
data. A redundancy group is also divided into logical units (LUNs), addressable by the host. See
the HP Virtual Array VA7100 User And Service Guide for more information.