Brocade Fabric OS Administrator's Guide Supporting Fabric OS v6.3.0 (53-1001336-02, November 2009)

Fabric OS Administrator’s Guide 39

53-1001336-02

Inter-chassis links

For additional information on ICLs, see the Brocade DCX Data Center Backbone Hardware

Reference Manual.

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

• 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.

If one ICL is broken but there is a regular ISL, the triangular topology still holds given the ISL cost is

lower than the total cost through the ICL linear topology. If a direct ICL link between two switches is

broken the triangular topology is considered broken when the ISL path between the two switches is

a multiple hop. In this case the triangular topology broken message will still be posted independent

of the cost of the ISL path being lesser or greater than the ICL path between the two switches.

Refer to the Brocade DCX Backbone Hardware Reference Manual and the Brocade DCX-4S

Backbone Hardware Reference Manual for instructions on how to cable ICLs.

TABLE 5 LED behavior

LED Color Description Action

Status

Black No connection with peer blade. NA

Green ICL connection with peer blade is

good.

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.