B: It is recommended to enable NAT on FortiGate policies. This is because the Azure load balancer uses a hash-based algorithm to distribute traffic to the FortiGate instances, and it relies on the source and destination IP addresses and ports of the packets1. If NAT is not enabled, the source IP address of the packets will be the same as the load balancer's frontend IP address, which will result in uneven distribution of traffic and possible asymmetric routing issues1. Therefore, it is recommended to enable NAT on the FortiGate policies to preserve the original source IP address of the packets and ensure optimal load balancing and routing1. D. It supports session synchronization for handling asynchronous traffic. This means that the FortiGate instances can synchronize their session tables with each other, so that they can handle traffic that does not follow the same path as the initial packet of a session2. For example, if a TCP SYN packet is sent to FortiGate A, but the TCP SYN-ACK packet is sent to FortiGate B, FortiGate B can forward the packet to FortiGate A by looking up the session table2. This feature allows the FortiGate instances to handle asymmetric traffic that may occur due to the Azure load balancer's hash-based algorithm or other factors.
The other options are incorrect because:
* It does not use the vdom-exception command to exclude the configuration from being synced. The vdom-exception command is used to exclude certain configuration settings from being synchronized between FortiGate devices in a cluster or a high availability group3. However, in this scenario, the FortiGate devices are not in a cluster or a high availability group, but they are standalone devices with standalone configuration synchronization enabled. This feature allows them to synchronize most of their configuration settings with each other, except for some settings that identify the FortiGate to the network, such as the hostname.
* It does not use the FGCP protocol. FGCP stands for FortiGate Clustering Protocol, which is used to synchronize configuration and state information between FortiGate devices in a cluster or a high availability group. However, in this scenario, the FortiGate devices are not in a cluster or a high availability group, and they use standalone configuration synchronization instead of FGCP.

B: Add route destination 0.0.0.0/0 to target the transit gateway. This will ensure that the Customer VPC FortiGate VM sends all the outbound internet traffic through the Security VPC, where it can be inspected by the Security VPC FortiGate VMs1. The transit gateway is a network device that connects multiple VPCs and on-premises networks in a hub-and-spoke model2. D. Deploy an internet gateway, associate an EIP in the private subnet, edit route tables, and add a new route destination 0.0.0.0/0 to the target internet gateway. This will allow inbound HTTPS access to the Customer VPC FortiGate VM from the internet, by creating a public route for the private subnet where the FortiGate VM is located3. An internet gateway is a service that enables communication between your VPC and the internet4. An EIP is a public IPv4 address that you can allocate to your AWS account and associate with your resources. E. Deploy an internet gateway, associate an EIP in the public subnet, and attach the internet gateway to the Customer VPC. This will also allow inbound HTTPS access to the Customer VPC FortiGate VM from the internet, by creating a public route for the public subnet where the FortiGate VM is located3. This is an alternative solution to option D, depending on which subnet you want to use for the FortiGate VM.
The other options are incorrect because:
* Adding a route with your local internet public IP address as the destination and target transit gateway will not allow inbound HTTPS access to the Customer VPC FortiGate VM from the internet, because it will only apply to traffic coming from your specific IP address, not from any other source on the internet1. Moreover, it will not ensure that the outbound internet traffic goes through the Security VPC, because it will only apply to traffic going to your specific IP address, not to any other destination on the internet1.
* Adding a route with your local internet public IP address as the destination and target internet gateway will not allow inbound HTTPS access to the Customer VPC FortiGate VM from the internet, because it will bypass the Security VPC and send the traffic directly to the Customer VPC1. Moreover, it will not ensure that the outbound internet traffic goes through the Security VPC, because it will only apply to traffic going to your specific IP address, not to any other destination on the internet1.

The correct answer is A and C. A transport attachment and a connect attachment are necessary to connect a transit gateway to an existing VPC with BGP.
According to the AWS documentation for Transit Gateway, a transit gateway is a network transit hub that connects VPCs and on-premises networks. To connect a transit gateway to an existing VPC with BGP, you need to do the following steps:
* Create a transport attachment. A transport attachment is a resource that connects a VPC or VPN to a transit gateway. You can specify the BGP options for the transport attachment, such as the autonomous system number (ASN) and the BGP peer IP address.
* Create a connect attachment. A connect attachment is a resource that enables you to use your own appliance to provide network services for traffic that flows through the transit gateway. You can use a connect attachment to route traffic between the transport attachment and your appliance using GRE tunnels and BGP.
The other options are incorrect because:
* A BGP attachment is not a valid type of attachment for a transit gateway. BGP is a protocol that enables dynamic routing between the transit gateway and the VPC or VPN.
* A GRE attachment is not a valid type of attachment for a transit gateway. GRE is a protocol that encapsulates packets for tunneling purposes. GRE tunnels are established between the connect attachment and your appliance.
[Transit Gateways - Amazon Virtual Private Cloud] : [Transit Gateway Connect - Amazon Virtual Private Cloud]

* Transit Gateway Connect Specificity: AWS Transit Gateway Connect is a specific feature designed to streamline the integration of SD-WAN appliances and third-party virtual appliances into your Transit Gateway.expand_more It utilizes a specialized attachment type.exclamation
* BGP's Role: While Transit Gateway Connect attachments leverage BGP for dynamic routing, BGP itself is a routing protocol and not the core connectivity mechanism in this context.
* GRE Tunneling: GRE is a tunneling protocol commonly used with Transit Gateway Connect attachments to encapsulate traffic.

The two best connection solutions available between your company headquarters, branch sites, and the Azure vWAN hub are A. ExpressRoute and E. VPN Gateway.
According to the Azure documentation for Virtual WAN, ExpressRoute and VPN Gateway are two of the supported connectivity options for connecting your on-premises sites and Azure virtual networks to the Azure vWAN hub1. These options provide secure, reliable, and high-performance connectivity for your network traffic.
ExpressRoute is a service that lets you create private connections between your on-premises sites and Azure.ExpressRoute connections do not go over the public internet, and offer more reliability, faster speeds, lower latencies, and higher security than typical connections over the internet2.
VPN Gateway is a service that lets you create encrypted connections between your on-premises sites and Azure over the internet using IPsec/IKE protocols.VPN Gateway also supports point-to-site VPN connections for individual clients using OpenVPN or IKEv2 protocols3.
The other options are incorrect because:
* GRE tunnels are not a supported connectivity option for Azure vWAN. GRE is a protocol that encapsulates packets for tunneling purposes.GRE tunnels are established between the connect attachment and your appliance in Azure vWAN4.
* SSL VPN connections are not a supported connectivity option for Azure vWAN. SSL VPN is a type of VPN that uses the Secure Sockets Layer (SSL) protocol to secure the connection between a client and a server.SSL VPN is not compatible with the Azure vWAN hub5.
* An L2TP connection is not a supported connectivity option for Azure vWAN. L2TP is a protocol that creates a tunnel between two endpoints at the data link layer (Layer 2) of the OSI model.L2TP is not compatible with the Azure vWAN hub.
1:Azure Virtual WAN Overview | Microsoft Learn2: [ExpressRoute overview - Azure ExpressRoute | Microsoft Docs]3: [VPN Gateway - Virtual Networks | Microsoft Azure]4: [Transit Gateway Connect - Amazon Virtual Private Cloud]5: [SSL VPN - Wikipedia] : [Layer 2 Tunneling Protocol - Wikipedia]