Building A Fabric; Overview; Principal Switch Selection - HP 5920 SERIES Fc And Fcoe Configuration Manual

Building a fabric

Overview

A fabric transmits data for servers and disk devices. When building a fabric, you must perform the
following tasks:
• Assign a domain ID to each FC switch in the fabric.
Assign an FC address to each node connected to the fabric.
•
You can build a fabric through one of the following modes:
Dynamic mode—A principal switch is automatically selected to assign domain IDs to all switches in
•
the fabric, and then each switch assigns FC addresses to the N_Ports connected to it. The dynamic
mode enables centralized network management and is applicable to large-sized networks.
Static mode—You must manually assign domain IDs to all switches in the fabric, and then each
•
switch assigns FC addresses to the N_Ports connected to it. The static mode avoids network flapping,
but it is applicable only to simple, small-sized networks. This mode does not involve a principal
switch selection process.
Figure 24 Fabric building workflows

Principal switch selection

During the dynamic fabric building process, it is the principal switch that assigns domain IDs to all
switches in the network.
The switch with the highest priority is selected as the principal switch. When multiple switches have the
same priority, the switch with the smallest WWN is selected.
The principal switch selection process is as follows:
When the principal switch selection starts, each switch performs the following operations:
1.
Considers itself to be the principal switch.
Records itself in the principal switch information.
Starts the Principal Switch Selection Timer (PSST), which is 10 seconds.
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