Allied Telesis AT-GS950/24 User Manual page 162

Chapter 11: LACP Port Trunks
the maximum number for the AT-GS950/24 switch, you should
assign the other vendor's device a higher system LACP priority
than your AT-GS950/24 switch. This can help avoid a conflict
between the devices if some ports are placed in the standby mode
when the devices create the trunk. For background information,
refer to "System Priority" on page 159.
LACPDU packets are transmitted as untagged packets.
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