Troubleshooting Tip: Unable to establish LAG between FortiSwitch/FortiGate and Meraki

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Description	This article describes a potential issue that may be faced when attempting to create a LAG between a FortiSwitch and Meraki where the Meraki device blocks the ports upon attempting to establish a LAG. This document may also be applicable between FortiGate devices and Meraki devices.
Scope	FortiSwitch, FortiGate.
Solution	With the default configuration, Meraki does not establish the LAG group if it receives a negotiated PDU with priority greater than itself, and places the ports in a blocking state.    When attempting to establish a LAG, FortiSwitch sends an LACP PDU with priority 65535: By default, Meraki sends an LACP PDU with priority of 32678:  Meraki will not establish the LAG group if it receives a negotiated PDU with priority greater than itself, and will place the ports in blocking state. Resolution: In the Meraki port or aggregation group settings, change the 'Enforce LACP' setting on the Meraki port side and set the value to 'Disabled'. If the Enforce LACP option cannot be seen, reach out to Meraki support for assistance to reveal option visibility.