Figure 19: Unsupported Trunk With Too Many Stacking Ports - Allied Telesis SwitchBlade x908 GEN2 Installation Manual

Chapter 2: Virtual Chassis Stacking
Chassis 1
Chassis 2
Figure 19. Unsupported Trunk with Too Many Stacking Ports
 You can use any line card in the chassis for the trunk.
Furthermore, as stated earlier, the ports of the trunk can be from
different cards in a chassis, so long as all the cards are the same
model.
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