First of all you need to have at least 1 port on each switch available.

If you want multiple ISLs you might need an extra truning license (Brocade).

On Cisco it's a best practice to put the ISL ports in VSAN 1 and make sure that only a specific set of VSANs are allowed over the link.

Then you need to make sure the ISL ports are E ports.

Then you need to make sure both switches have different domain ids (Brocade).

On Cisco you need to define a portchannel if multiple ports are used.

Enable both ports and watch the fabric grow larger .

Does this help ?

Thanks for this reply,

Can you put in steps to add switch to the fabric.

and please answer

"What effect does this action have to the existing fabric and other switches in this fabric? How do we make this newly added switch to talk and introduce to other switches?" How does the fabric get affected ( any rebuild needed?)

AFAIK each switch must be having unique ID ...please confirm.

Cheers,

A few things to consider to make sure that you can ISL successfully:

* The ports on both switches must be configured to allow E type connections. This should be the default
* The zoning database from each switch will merge, so you should ensure there are no zones that will conflict. In your case one switch likely won't have any zones defined at first anyway, sp it shouldn't be an issue
* You can't ISL two switches together if the Domain IDs are the same. Make sure the Domain ID on the new switches are different from the existing switches.
* You will want to confirm that the "Compatibility" mode on both switches are consistent. This can be found on the Compatibility tab under Configuration when you enable Advanced Mode in the Switch Administration dialog (this is for the Web interface which I'm most familiar with). You are probably going to want both set to Brocade Native.

ISLing is actually very simple. Assuming that the configuration of the switch ports has not been changed to prevent "E" type connections, you can ISL two switches together by simply connecting a port on each with a patch cable. If the ISL is successful, the two "fabrics" (in this case each fabric starts out as an individual switch) will merge to become a single fabric. The Zoning databases will merge and the switches will synchronize. You can tell for sure that this has happened by looking in the interface to see the port type. A port with storage or a host logged in will be an F port. If the ISL has established you will see the port configured as an E port.