Configuring Traffic Mirroring Target/Filter/Session:

Go to VPC > Traffic mirror targets and click Create traffic mirror target.
Under Choose target > target, select the secondary network interface of FortiNDR in private subnet.
In the VPC/ Traffic Mirror Filter, select Create traffic mirror filter.
Configure inbound/outbound traffic filter for NDR. E.G All traffic will be mirrored as illustrated in following figure.
In the VPC/ Traffic Mirror Session, click Create traffic mirror session.
Select designated network interface for mirror source.
Select the previously created mirror target and mirror filter. Configure Session Number, VNI and Packet Length as required.

Go to VPC > Traffic mirror targets and click Create traffic mirror target.

Under Choose target > target, select the secondary network interface of FortiNDR in private subnet.

In the VPC/ Traffic Mirror Filter, select Create traffic mirror filter.

Configure inbound/outbound traffic filter for NDR. E.G All traffic will be mirrored as illustrated in following figure.

In the VPC/ Traffic Mirror Session, click Create traffic mirror session.

Select designated network interface for mirror source.

Select the previously created mirror target and mirror filter. Configure Session Number, VNI and Packet Length as required.