Technical Tip: One out of two managed FortiSwitches are not coming online on FortiGate with interface type 802.3ad aggregate

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Description	This article describes config error where two FortiSwitches are connected to 802.3ad aggregate (dedicated to FortiSwitch) interface on FortiGate.
Scope
Solution	In some cases, requirement is to manage two FortiSwitches directly to the FortiGate without any inter switch link (ISL) between the switches. The correct interface type which should be configured on the FortiGate is hardware switch and not 802.3ad aggregate. https://docs.fortinet.com/document/fortiswitch/7.0.4/devices-managed-by-fortios/801202/single-fortig... If 802.3ad aggregate interface type is selected - map 2 ports as members of aggregate interface - connect one port to FSW1 and other port to FSW2, only one of the two FortiSwitches will come online. Reason: 802.3ad aggregate type means logical single interface.