HP StorageWorks 2/64 HP StorageWorks Fabric OS 5.x Command Reference Guide (AA - Page 815

RAID Redundant array of independent disks. A collection of disk drives that appear as a single volume to the server and are fault tolerant through mirroring or parity checking. See also JBOD. RAIT Redundant array of independent tapes. RCS Reliable Commit Service. Refers to HP-specific ILS command code. RCS_SFC RCS Stage Fabric Config. Refers to HP-specific ILS command code. receiver A device that performs detection and signal processing. redundancy Having multiple occurrences of a component to maintain high availability (HA). remote switch An optional product for long-distance fabrics, requiring a Fibre Channel-to-ATM or SONET gateway. repeater A circuit that uses a recovered clock to regenerate and transmit an outbound signal. request rate The rate at which requests arrive at a servicing entity. resilience A fabric's ability to adapt to or tolerate a failure of a component within the fabric. resilient core/edge Two or more switches acting as a core to interconnect multiple edge switches. Nodes attach to topology the edge switches. responder The N_Port with which an exchange originator attempts to communicate. retimer A circuit that uses an independent clock to generate outbound signals. return loss The ratio (expressed in dB) of incident power to reflected power, when a component or assembly is introduced into a link or system. Can see optical power or to electrical power in a specified frequency range. RLS Read Link Status. route As it applies to a fabric, the communication path between two switches. Might also apply to the specific path taken by an individual frame, from source to destination. See also FSPF. routing The assignment of frames to specific switch ports, according to frame destination. RR_TOV Resource recovery timeout value. The minimum time a target device in a loop waits after an LIP before logging out an SCSI initiator. See also E_D_TOV, R_A_TOV. RSCN Registered state change notification. A switch function that allows notification of fabric changes to be sent from the switch to specified nodes. The fabric controller issues RSCN requests to N_Ports and NL_Ports, but only if they have registered to be notified of state changes in other N_Ports and NL_Ports. This registration is performed via the State Change Registration (SCR) Extended Link Service. An N_Port or NL_Port can issue an RSCN to the fabric controller without having completed SCR with the fabric controller. RTWR Reliable transport with response. Might appear as a task in portLogDump command output. running disparity A binary parameter indicating the cumulative disparity (positive or negative) of all previously issued transmission characters. RW Read/write. Refers to access rights. RX Receiving frames. RX_ID Responder exchange identifier. A 2-byte field in the frame header that can be used by the responder of the exchange to identify frames as being part of a particular exchange. Fabric OS 5.x command reference guide 815