Host adapter

In computer hardware, a host controller, host adapter, or host bus adapter (HBA), connects a computer system bus, which acts as the host system, to other network and storage devices. The terms are primarily used to refer to devices for connecting SCSI, SAS, NVMe, Fibre Channel and SATA devices. Devices for connecting to FireWire, USB and other devices may also be called host controllers or host adapters. Host adapters can be integrated in the motherboard or be on a separate expansion card. The term network interface controller (NIC) is more often used for devices connecting to computer networks, while the term converged network adapter can be applied when protocols such as iSCSI or Fibre Channel over Ethernet allow storage and network functionality over the same physical connection. A connects a host system and a peripheral SCSI device or storage system. These adapters manage service and task communication between the host and target. Typically a device driver, linked to the operating system, controls the host adapter itself. In a typical parallel SCSI subsystem, each device has assigned to it a unique numerical ID. As a rule, the host adapter appears as SCSI ID 7, which gives it the highest priority on the SCSI bus (priority descends as the SCSI ID descends; on a 16-bit or "wide" bus, ID 8 has the lowest priority, a feature that maintains compatibility with the priority scheme of the 8-bit or "narrow" bus). The host adapter usually assumes the role of SCSI initiator, in that it issues commands to other SCSI devices. A computer can contain more than one host adapter, which can greatly increase the number of SCSI devices available. Major SCSI adapter manufacturers are HP, ATTO Technology, Promise Technology, Adaptec, and LSI Corporation. LSI, Adaptec, and ATTO offer PCIe SCSI adapters which fit in Apple Mac, on Intel PCs, and low-profile motherboards which lack SCSI support due to the inclusion of SAS and/or SATA connectivity. The term host bus adapter (HBA) may be used to refer to a Fibre Channel interface card.

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related concepts (33)

Related lectures (6)

Quantum Langevin Equations

Covers the derivation of quantum Langevin equations and input-output formalism in open quantum systems.

Monitoring with Icinga2

Explores the monitoring of a new VM and the use of Icinga2 for critical alerts and incident management.

Statistical Physics IV: Part II

Delves into advanced statistical physics concepts, exploring complex systems behavior and dissipative dynamics.

Solid-state drive

A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies to store data persistently, typically using flash memory, and functioning as secondary storage in the hierarchy of computer storage. It is also sometimes called a semiconductor storage device, a solid-state device or a solid-state disk, even though SSDs lack the physical spinning disks and movable read–write heads used in hard disk drives (HDDs) and floppy disks. SSD also has rich internal parallelism for data processing.

Hot swapping

Hot swapping is the replacement or addition of components to a computer system without stopping, shutting down, or rebooting the system; hot plugging describes the addition of components only. Components which have such functionality are said to be hot-swappable or hot-pluggable; likewise, components which do not are cold-swappable or cold-pluggable. Most desktop computer hardware, such as CPUs and memory, are only cold-pluggable.

Host adapter