Examples With Multiple Loop Prevention Switches - Allied Telesis GS910/XST Series Installation And User Manual

Chapter 1: Product Description
Examples with
In examples shown in Figure 12, multiple GS910/XST series switches
form links and all switches are Loop Prevention enabled. Switch C has a
Multiple Loop
lower MAC address than Switch A and Switch B; Switch B has a lower
Prevention
MAC address than Switch A. First, these switches elect a root switch by
Switches
comparing the MAC addresses. In cases 1 and 2, Switch B is elected as a
root switch; in case 3, Switch C is elected as a root switch. Then the root
switch initiates Loop Prevention frames and non-root switches update the
frames and forward them. When detecting a loop, the root switch runs the
Loop Prevention algorithm to decide which port to block, and blocks a port
or ports to relieve the loop.
x
Figure 12. Multiple GS910/XST Series Switches for Loop Prevention
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