Technical data

private arbitrated loops (looplets) that are interconnected by a fabric. A
private loop is formed by logically connecting ports on up to two switches.
______________________ Note _______________________
QuickLoop is not supported in a Tru64 UNIX Version 5.1A
configuration or TruCluster Server Version 5.1A configuration.
6.5 Zoning
This section provides a brief overview of zoning.
A zone is a logical subset of the Fibre Channel devices that are connected
to the fabric. Zoning allows partitioning of resources for management and
access control. In some configurations, it may provide for more efficient use
of hardware resources by allowing one switch to serve multiple clusters or
even multiple operating systems. Zoning entails splitting the fabric into
zones, where each zone is essentially a virtual fabric.
Zoning may be used:
• When you want to set up barriers between systems of different operating
environments or uses, for instance to allow two clusters to utilize the
same switch.
• To create test areas that are separate from the rest of the fabric.
• To provide better utilization of a switch by reducing the number of
unused ports.
______________________ Note _______________________
Any initial zoning must be made before connecting the host bus
adapters and the storage to the switches, but after zoning is
configured, changes can be made dynamically.
6.5.1 Switch Zoning Versus Selective Storage Presentation
Switch zoning and the selective storage presentation (SSP) feature of the
HSG80 controllers have similar functions.
Switch zoning controls which servers can communicate with each other
and each storage controller host port. SSP controls which servers will have
access to each storage unit.
6–18 Using Fibre Channel Storage