Joe,
The Fibre Channel Adapter is an A6795A. This is a 2GB adapter that uses LC
connectors. (LC is the smaller connector. SC is the large one.) The cost,
last I looked, was was in the $2,100 range.

This adapter will allow you to connect to your disc drives. You can do this
through a switch, a hub or direct connect. Different technologies exist to
connect your server to your storage. FC-AL, Fibre Channel Arbitrated Loop,
is the default. If you connect through a direct connection or a hub you will
have an FC-AL connection. You can also use FC-AL through a switch. Brocade
switches also allow what they call QuickLoop which is a hybrid of FC-AL and
FC-SW. FC-SW is switch mode or fabric mode.

The difference between fabric and FC-AL is that FC-AL is a series of
addresses connected together. Each is required to negotiate for access to
the loop. The device with the lowest WWN, World Wide Name always wins. This
can cause bottlenecks. All Fabric devices have direct access to each other
not to a loop. They are connected to what is called a cloud. Through this
amorphous connection all devices send and receive to all other devices.

There are limits to how many devices, i.e. logical units, each adapter can
handle. The maximum allowed may not give the best performance. YMMV.

The N-Class has 12 adapter slots. The A-Class has 4 adapter slots. I am not
sure if you can put an A6795A in slot 1 on the A-Class.

Work For Peace

Yosef Rosenblatt

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