iSCSI (Internet Small Computer Systems Interface) is a protocol that transmits SCSI commands over IP networks. The technology facilitates the connection of data storage systems over long distances, which makes it an important element of data storage networks (SAN).
How iSCSI works
The principle of operation of iSCSI is to encapsulate SCSI commands in TCP/IP packets, which are then transmitted over an Ethernet network. The process includes two main components: the iSCSI initiator and the iSCSI target.
An iSCSI initiator is a client—side component that sends SCSI commands to an iSCSI target device. The target then processes these commands and returns the requested data to the initiator.
iSCSI versus SCSI
Unlike conventional SCSI, which uses parallel cables for connection, iSCSI takes advantage of widespread Ethernet networks. Due to this, iSCSI is a cost—effective and adaptable solution for organizations of different scales.
In addition, the use of standard iSCSI network equipment reduces the need for specialized equipment, which makes it a more cost-effective solution compared to traditional SCSI.
Advantages of iSCSI
- Scalability. iSCSI makes it easy to increase storage capacity without significant hardware changes.
- Economic efficiency. Using the existing Ethernet infrastructure, iSCSI reduces the need for specialized hardware.
- Flexibility. The use of IP networks in iSCSI allows you to store and retrieve data over long distances.
iSCSI Implementation
The iSCSI implementation involves configuring the iSCSI initiator on the server and configuring the iSCSI target device on the storage device. Most modern operating systems, including Windows, Linux, and macOS, come with built-in iSCSI initiators. On the other hand, setting up an iSCSI target requires an iSCSI-enabled storage device, such as a network attached storage device (NAS) or a dedicated iSCSI device.