Fabric Services

Fibre Channel switches, regardless of the manufacturer, provide a common set of services as defined in the Fibre Channel standards. These services are available at certain pre-defined addresses. Some of these services are Fabric Login Server, Fabric Controller, Name Server, and Management Server.

The Fabric Login Server is located at the predefined address of FFFFFE and is used during the initial part of the node’s fabric login process.

The Name Server (also known as Distributed Name Server) is located at the predefined address FFFFFC and is responsible for name registration and management of node ports. Each switch exchanges its Name Server information with other switches in the fabric to maintain a synchronized, distributed name service.

Fabric Controller located at the predefined address FFFFFD. The Fabric Controller provides services to both node ports and other switches. The Fabric Controller is responsible for managing and distributing Registered State Change Notifications (RSCNs) to the node ports registered with the Fabric Controller. If there is a change in the fabric, RSCNs are sent out by a switch to the attached node ports. The Fabric Controller also generates Switch Registered State Change Notifications (SW-RSCNs) to every other domain (switch) in the fabric. These RSCNs keep the name server up-to-date on all switches in the fabric.

Management Server located at the predefined address FFFFFA. The Management Server is distributed to every switch within the fabric. The Management Server enables the FC SAN management software to retrieve information and administer the fabric.

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