Brocade Communications Systems ICX 6430 Hardware Installation Manual page 45

Topology 3 is almost identical to topology 2 except that the "horizontal" substack is not connected to the
second ICX 6610 device either by design or because the link is broken. This is still a valid topology.
FIGURE 36 Topology 3: linear and ring
Topology 4: ring with one backbone device
In the figure below, one ICX 6610 device forms the backbone and there are six ICX 6450 peripheral
devices in a ring topology. There is one substack that contains all six peripheral devices.
Topology 4 shows that you can have a mixed stack with only one ICX 6610 device, although it does not
provide high availability or resiliency for the stack because there is no standby controller.
FIGURE 37 Topology 4: ring with one backbone device
Topology recommendations
Consider these factors when you implement a topology:
• Limit the number of VLANs of peripheral devices to reduce broadcast and multicast packets
flooding to the peripheral devices.
• Broadcast and multicast packets of a VLAN are flooded to a substack if the substack has any ports
in the VLAN. For this reason, you should limit (localize) VLAN association of substack ports.
For example, substacks 1 and 2 have ports in VLAN 10, 11, 12, and 13. In this case, you should
arrange the VLAN port association so that substack 1 ports are in VLAN 10, 11, and 12 and substack 2
Brocade ICX 6430 and ICX 6450 Stackable Switches Hardware Installation Guide
53-1003079-01
Topology 4: ring with one backbone device
43