Alaxala AX2200S Series Configuration Manual page 363

Figure 19-17 Problems that occur during unidirectional link faults
Loop guard functionality transitions the status of a port for which BPDU reception has been
cut off to a non-transferrable status until another BPDU is received. When BPDU reception
starts, operation resumes as a normal Spanning Tree target port.
The loop guard functionality does not run on a port for which the root guard functionality is
set, or when the PortFast functionality is set for the Switch or for the port.
The following table describes the loop guard operating conditions.
Table 19-21 Operating conditions of loop guard
PortFast Configuration definition
Functiona
lity
Configuration for each port
(spanning-tree guard)
Enabled Loop guard is set (loop)
Guard disabled (none)
Configuration for each
switch
(spanning-tree loopguard
default)
(Priority is given to the
configuration for each port.)
19 Spanning Tree Protocol
Loop guard
operation
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