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Figure 115. Switch A11 is Down
Consider the following illustration where both stack ports on A1-1 are down. When it happens, A1-1 becomes a standalone
Master unit and A1-2 and A1-3 form a separate stack. A2-1 is not notified of this change because A1-1 continues to send LACP
PDUs with the old stack Master unit MAC address. As Server1 is not aware of the stack link failure in A1-1, it continues to send
traffic leading to traffic loss.
Figure 116. Both Stack Links are Down
Dell EMC Networking OS provides an option to enable the switch to detect when both stack links fail and shuts down all uplink
(external) and downlink (internal) ports. If one of the stack ports come up, the system brings up all the server facing ports and
uplink ports irrespective of the earlier status.
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Stacking