Allied Telesis AlliedWare Plus Operating System Version 5.4.4C (x310-26FT,x310-26FP,x310-50FT,x310-50FP) - Manual (Page 433)

VLAN Commands
Software Reference for x310 Series Switches
C613-50046-01 REV A AlliedWare Plus TM Operating System - Version 5.4.4C 17.5
Usage EPSR, Loop Protection and MAC Thrashing protection do not usually need to be
configured on a switch, because they perform similar functions—each prevents network
loops by blocking a selected port for each (loop containing) VLAN.
However, if more than one of these three features is configured on a switch, you can use
this command to prioritize either EPSR or Loop Protection when their effects on a port
would conflict and override each other. Previously, each protocol could set a port to
forwarding for a VLAN, sometimes overriding the previous setting by another protocol to
block the port. This could sometimes lead to unexpected broadcast storms.
Now, when a protocol is set to have the highest priority over a data VLAN on a port, it will
not allow other protocols to put that port-vlan into a forwarding state if the highest
priority protocol blocked it.
The priority mechanism is only used for blocking-to-forwarding transitions; protocols
remain independent on the forwarding-to-blocking transitions.
Example To prioritize EPSR over Loop Protection or MAC Thrashing protection settings, so that Loop
Protection or MAC Thrashing protection cannot set a port to the forwarding state a VLAN
if EPSR has set it to the blocking state, use the commands:
To prioritize Loop Protection over EPSR or MAC Thrashing protection settings, so that EPSR
or MAC Thrashing protection cannot set a port to the forwarding state a VLAN if Loop
Protection has set it to the blocking state, use the commands:
To set EPSR, Loop Protection, and MAC Thrashing protection protocols to have equal
priority for port forwarding and blocking, which allows the protocols to override each
other to set a port to the forwarding or blocking states, use the commands:
To restore the default highest priority protocol back to the default of EPSR, use the
commands:
Related Commands show port-vlan-forwarding-priority
awplus# configure terminal
awplus(config)# port-vlan-forwarding-priority epsr
awplus# configure terminal
awplus(config)# port-vlan-forwarding-priority loop-
protection
awplus# configure terminal
awplus(config)# port-vlan-forwarding-priority none
awplus# configure terminal
awplus(config)# no port-vlan-forwarding-priority