Perc 4 management software

Table Features for Drive Roaming. Table displays the PERC 4 hardware architecture features. Table Hardware Architecture Features. Table displays the PERC 4 array performance features. Table Array Performance Features. Table describes the fault tolerance capabilities of the PERC 4 controllers. Table Fault Tolerance Features. Table describes the features offered by the utilities used for RAID management.

Table Software Utilities Features. These controllers include a Disk Operating System DOS software configuration utility and drivers for the following operating systems:. Up to simultaneous commands with elevator sorting and concatenation of requests per SCSI channel. Software utilities enable you to manage and configure the RAID system, create and manage multiple disk arrays, control and monitor multiple RAID servers, provide error statistics logging, and provide online maintenance.

The utilities include:. An extra bit added to a byte or word to reveal errors in storage in RAM or disk or transmission. Parity is used to generate a set of redundancy data from two or more parent data sets. The redundancy data can be used to reconstruct one of the parent data sets. However, parity data does not fully duplicate the parent data sets. In RAID, this method is applied to entire drives or stripes across all disk drives in an array.

Parity consists of dedicated parity, in which the parity of the data on two or more drives is stored on an additional drive, and distributed parity, in which the parity data are distributed among all the drives in the system. If a single drive fails, it can be rebuilt from the parity of the applicable data on the remaining drives.

A complete or partial representation of a logical drive, usually represented to a user by an operating system as a physical disk. Also called a logical volume. It is an ideal RAID solution for the internal storage of Dell's workgroup, departmental, and enterprise systems. A hard drive. A physical disk is used to store information, data , in a non-volatile and randomly accessible memory space.

The ability of adapters to detect when hard drives have been moved to different slots in the storage enclosure, such as after a hot swap. A set of formal rules describing how to transmit data, generally across a network or when communicating with storage sub-systems. Low-level protocols define the electrical and physical standards to be observed, bit- and byte-ordering, and the transmission and error detection and correction of the bit stream.

High-level protocols deal with the data formatting, including the message syntax, the terminal to computer dialogue, character sets, sequencing of messages, etc. The RAID array appears to the controller as a single storage unit.

A style of redundancy applied to an array. It can increase the performance of a logical drive though it may decrease usable capacity. Each logical array must have a RAID level assigned to it. A memory caching capability in some adapters that allows them to read sequentially ahead of requested data and store the additional data in cache memory, anticipating that the additional data will be needed soon.

Read-Ahead supplies sequential data faster, but is not as effective when accessing random data. A condition in which a workable hard drive is neither online nor a hot spare and is available to add to an array or to designate as a hot spare.

The regeneration of all data to a replacement disk from a failed disk in a logical drive with a RAID level 1, 5, 10 or 50 array. A disk rebuild normally occurs without interrupting normal operations on the affected logical drive, though some degradation of performance of the disk subsystem can occur. The act of remaking a logical drive after changing RAID levels or adding a physical drive to an existing array. The provision of multiple interchangeable components to perform a single function to cope with failures and errors.

Common forms of hardware redundancy are disk mirroring, implementations of parity disks or distributed parity. A component or collection of components in a system or subsystem that is always replaced as a unit when any part of the collection fails.

Typical replacement units in a disk subsystem include disks, adapter logic boards, power supplies and cables.

Small Computer System Interface A processor-independent standard for system-level interfacing between a computer and intelligent devices, such as hard disks, floppy disks, CD-ROM, printers, and scanners. SCSI can connect up to 15 devices to a single adapter or host adapter on the computer's bus.

SCSI transfers 8, 16 or 32 bits in parallel and can operate in either asynchronous or synchronous modes.

Each adapter controls two SCSI channels. Segmentation of logically sequential data, such as a single file, so that segments can be written to multiple physical devices in a round-robin fashion. This technique is useful if the processor can read or write data faster than a single disk can supply or accept it.

While data is being transferred from the first disk, the second disk can locate the next segment. Up to simultaneous commands with elevator sorting and concatenation of requests per SCSI channel. They include:. The firmware automatically detects and rebuilds failed drives. This can be done transparently with hot spares. See your system documentation for more information. Write-back, Write-through, Adaptive read-ahead, Non read-ahead, Read-ahead.

Single command can transfer data to and from different memory locations.