Figure 12: Example Of A Stack Trunk Of Ports On Multiple Line Cards - Allied Telesis AT-SB*908 GEN2 Installation Manual

AT-SBx908 GEN2 Installation Guide for Virtual Chassis Stacking
 You can further improve the resiliency of trunks by distributing the
ports onto multiple cards in a switch. This makes it possible for
trunks to continue functioning, though at reduced bandwidths, even
if line cards with trunk ports fail. The example in Figure 12 is a
stack of three switches with a trunk of two links from switch-to-
switch, on different line cards.
Chassis 1
Chassis 2
Chassis 3
Figure 12. Example of a Stack Trunk of Ports on Multiple Line Cards
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