Optimizing Iscsi Overview - Dell PowerConnect 5524P User Manual

Optimizing iSCSI Overview

The Internet Small Computer System Interface (iSCSI) is an IP-based
storage networking standard for linking data storage facilities. By carrying
SCSI commands over IP networks, iSCSI is used to facilitate data transfers
over intranets, and to manage storage over long distances.
iSCSI can be used to transmit data over local area networks (LANs), wide area
networks (WANs), or the Internet, and can enable location-independent data
storage and retrieval.
Unlike traditional Fiber channels, which requires special-purpose cabling,
iSCSI can be run over long distances, using existing network infrastructure.
The protocol enables clients (called initiators) to send SCSI commands
(CDBs) to SCSI storage devices (targets) on remote servers. This enables
organizations to consolidate storage into data center storage arrays, while
providing hosts (such as database and web servers) with the illusion of
locally-attached disks.
The targets listen on a well-known TCP port (or any other TCP port that has
been explicitly specified) for incoming connections. The login process is
started when the initiator establishes a TCP connection to the desired target,
through the TCP port that was explicitly specified.
The group of iSCSI TCP connections that link an initiator with a target is
called an iSCSI session.
When you connect an EqualLogic device to the switch, and iSCSI
optimization is enabled, the switch automatically recognizes the port to
which the EqualLogic equipment is connected to, and configures the STP
Mode to RSTP to support fast network convergence.
Optimizing iSCSI
iSCSI optimization provides the following features:
• Ability to assign a specific QoS profile to the iSCSI flows
• Display of iSCSI session details (connections, initiator, target, and so on)
• Identification of (self-discovered) iSCSI sessions
• Identification of iSCSI session termination
• Identification of non-active iSCSI sessions
Dell PowerConnect 55xx Systems User Guide
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