Blocking A Port Affected By An External Loop - Allied Telesis AT-GS920/16 Installation And User Manual

GS920 Series Gigabit Ehternet Switch Installation and User's Guide
Blocking a Port
In the example shown in Figure 70, Switch A is the only switch that has
Loop Prevention enabled in the LAN and the other switches in the LAN
Affected by an
have Loop Prevention disabled.
External Loop
Since Switch A is the only switch with Loop Prevention enabled, it is by
definition the root switch. Port 1 of Switch A is blocked as a result.
Ax
Figure 70. Blocking a Port Affected by an External Loop
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