Q-Logic SB2A-16B Switch User Manual


 
3 – Planning
Multiple Chassis Fabrics
3-6 59021-08 B
D
3.4
Multiple Chassis Fabrics
By connecting switches together you can expand the number of available ports for
devices. Each switch in the fabric is identified by a unique domain ID, and the
fabric will automatically resolve domain ID conflicts. Because the Fibre Channel
ports are self-configuring, you can connect SANbox2-16 and other FC-SW-2
compliant switches together in a wide variety of topologies.
3.4.1
Optimizing Device Performance
When choosing a topology for a multiple chassis fabric, you should also consider
the locality of your server and storage devices and the performance requirements
of your application. Storage applications such as video distribution, medical record
storage/retrieval or real-time data acquisition can have specific latency or
bandwidth requirements. Refer to ”Performance” on page 3-4 for information
about latency and bandwidth. However, the highest performance is achieved on
Fibre Channel switches by keeping traffic within a single switch instead of relying
on ISLs. Therefore, for optimal device performance place devices on the same
switch under the following conditions:
Heavy I/O traffic between specific server and storage devices.
Distinct speed mismatch between devices such as the following:
A 2 Gbps server and a slower 1 Gbps storage device
A high performance server and slow tape storage device