With stacks of three or four switches, the number of physical links
in the trunk has to be the same on all switches. The example in
Figure 20 is a stack of three chassis with a valid trunk of two links
between chassis 1 and 2, chassis 2 and 3, and chassis 3 and 1.
Figure 20. Stack with Three Chassis
SBx908 GEN2 Installation Guide for Virtual Chassis Stacking
Chassis 1
Chassis 2
Chassis 3
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