Q-Logic 59021-05 B Manuale Utente

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59021-05 B
3-1
Section 3
Planning
Consider the following when planning a fabric:
„
Devices
„
Multiple chassis fabrics
„
Performance
„
Device access
„
Fabric management
„
Fabric security
3.1
Devices
When planning a fabric, consider the number of devices and the anticipated 
demand. This will determine the number of ports that are needed and in turn the 
number of switches. Consider how many and what types of switches are needed.
Consider the distribution of public and private devices as well as targets and 
initiators. Public devices have full Fibre Channel addressing capability, and 
therefore can communicate with any other public device on the fabric. An F_Port 
supports a single public device. An FL_Port can support up to 126 public devices 
in an arbitrated loop.
Private devices do not have full Fibre Channel addressing capability, only the 
Arbitrated Loop Physical Address (ALPA) portion. A TL_Port provides a proxy for 
a loop of up to 124 private target devices allowing communication with up to 63 
off-loop public initiator devices. Consider the number of private devices in the 
fabric and the number of off-loop devices with which the private devices must 
communicate.
The SANbox2-16 Fibre Channel switch uses SFP optical transceivers, but the 
device host bus adapters you are using may not. Consider whether the device 
adapters use SFP transceivers or Gigabit Interface Converters (GBIC), and 
choose fiber optic cable accordingly. Use LC-type cable connectors for SFP 
transceivers and SC-type cable connectors for GBIC transceivers.