Figure 9: Example Trunks For Stacks Of Two, Three, Or Four Switches - Allied Telesis AT-SBx908 Installation Manual

AT-SBx908 GEN2 Installation Guide for Virtual Chassis Stacking
Stack with Two
Chassis
Stack with Three
Chassis
Stack with Four
Chassis
Figure 9. Example Trunks for Stacks of Two, Three, or Four Switches

The trunk configuration is referred to as a ring because the last
switch in the stack is connected to the first switch, creating a loop.
This is the recommended configuration. It adds resiliency to the
stack because it enables a trunk to continue functioning even if a
link fails.
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