72 Fabric OS Administrator’s Guide
53-1001763-02
Inter-chassis links
4
The following ICL connections are not allowed:
ICL0 <--> ICL0
ICL1 <--> ICL1
Refer to the Brocade DCX Data Center Backbone Hardware Reference Manual for detailed ICL
connection information.
ICL ports can be used only with an ICL license. For more information on how license enforcement
occurs, see Chapter 16, “Administering Licensing”. After the addition or removal of a license, the
license enforcement is performed on the ICL ports only when you issue the portDisable or
portEnable commands on the switch for the ports. All ICL ports must be disabled, and then
re-enabled for the license to take effect. An ICL license must be installed on both platforms forming
the ICL connection.
There are two LEDs — a status LED and an attention LED — for each ICL connector port. The
following table describes the behavior of the LEDs.
The ICL ports appear as regular ports, with some restrictions. All port parameters associated with
ICL ports are static and all portCfg commands are blocked from changing any of the ICL port
parameters. The only management associated with ICL ports and cables is monitoring the status of
the LEDs on the ICL ports and any maintenance if the ATTENTION LED is blinking yellow. For
additional information about the LED status for blades and ports, see the Brocade DCX Hardware
Installation manual.
When you connect two Brocade Backbones, the following features are supported:
8 Gbps speed
Trunking
Buffer-to-buffer credit sharing
QoS

Supported topologies

The triangular topology is supported between three Brocade DCX or DCX-4S chassis. On an ICL
break the chassis that has the connections of the other two, is the main chassis. Any error
messages relating to a break in the topology will appear in this chassis’ RASlog.
TABLE 8 LED behavior
LED Color Description Action
Status Black No connection with peer blade. NA
Green ICL connection with peer blade is
good.
NA
Attention Black ICL is fully operational. NA
Blinking Yellow One or more links in the ICL
connection is NOT operational.
Reconnect the ICL cables
or replace the ICL cables.