IBM TotalStorage 201, User Reference Manual

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FIC (see File Image Capture).
Field-replaceable unit (FRU). An assembly that is replaced in its entirety when any one of its components fails. In
some cases, a field replaceable unit may contain other field replaceable units. Contrast with customer-replaceable unit
(CRU).
File Image Capture (FIC). Function that takes a file system clone and a read-only copy of the certain read-write
(active) file system. File Image Capture reflects the state of the file system at the time it was created.
File Image Restore. Function that allows a file system to revert to the state and contents of a previous File Image
Capture. This function can be used to recover a corrupted file system.
File Transfer Protocol (FTP). In the Internet suite of protocols, an application layer protocol that uses TCP and
Telnet services to transfer bulk-data files between machines or hosts.
FIR (see File Image Restore).
firewall. A logical barrier around systems in a network. A firewall consists of hardware, software, and a security policy
that control the access and flow of information between secure or trusted systems and nonsecure or untrusted
systems.
fixed-length record. A record having the same length as all other records with which it is logically or physically
associated.
flash memory. A memory chip that holds its content without power but must be erased in fixed blocks rather than
single bytes.
floating virtual connection (FVC). The ability to resume a virtual connection on a port other than the port
connection on which the original virtual connection was established.
frame alignment error. An error in a frame, indicated by a frame check sequence (FCS) indicator. When excessive
or missing bits occur during the reception of a frame, the frame is misaligned.
free disk. A physical disk that is not assigned as a hot-spare, as a standby hot-spare, or to a logical drive.
FRU (see field-replaceable unit).
FTP (see File Transfer Protocol).
FVC (see floating virtual connection).
G
gateway. A device that acts as a router, but occurs at the transport layer, to transfer packets between networks.
group definition. A list of directory numbers.
group definition ID. The identifier of a group definition.
group SAP. A single address assigned to a group of service access points (SAPs).
group separator (GS) character. The information separator intended to identify a logical boundary between groups.
H
hard failure. An error condition on a network that requires that the network be reconfigured or that the source of the
error be removed before the network can resume reliable operation. Synonym for hard error.
hertz (Hz). A unit of frequency equal to one cycle per second.
Note: In the United States, line frequency is 60 Hz or a change in voltage polarity 120 times per second; in Europe,
line frequency is 50 Hz or a change in voltage polarity 100 times per second.
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NAS 200 User’s Reference