Automatic ISL formation and hardware-based trunking
When a switch joins an Ethernet fabric, ISLs automatically form between directly connected switches within the fabric.
If more than one ISL exists between two switches, then Brocade ISL trunks can form automatically. All ISLs connected to the same neighboring Brocade switch attempt to form a trunk. The trunks are formed only when the ports belong to the same port group. No user intervention is necessary to form these trunks.
Refer to Configuring fabric interfaces for information about enabling and disabling ISLs and trunks.