Brocade Fabric OS Administrators Guide (Supporting Fabric OS v7.3.0) - Manual (Page 488)

FIGURE 72 ICL triangular topology with Brocade DCX 8510-8 chassis
During an ICL break in the triangular topology, the chassis that has the connections of the other two is
the main chassis. Any error messages relating to a break in the topology appear in the RASlog of the
main chassis.
For the Brocade DCX Backbone family only: If one ICL is broken but there is a regular ISL, the
triangular topology holds given that the ISL cost is lower than the total cost through the ICL linear
topology. If a direct ICL link between two chassis 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 is posted independently of the cost of the ISL path being lesser or greater
than the ICL path between the two switches.
Another form is the full nine-mesh topology shown in Figure 73 . This topology is supported by DCX
8510-8 Backbones only. (You can use DCX 8510-4 Backbones for a five-mesh topology.)
Inter-chassis Links
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