FCSS_SDW_AR-7.6 Exam Dumps - Fortinet Certified Solution Specialist Questions and Answers

To allow spokes in different hub-and-spoke groups to establish ADVPN shortcuts, the hubs must be configured to forward and send ADVPN shortcut offers. The key required settings on the hub are auto-discovery-forwarder (for VPNs to hubs) and auto-discovery-sender (for VPNs to spokes). This ensures the hub can facilitate and advertise ADVPN shortcut offers between spokes.

This configuration demonstrates a typical IPsec setup for SD-WAN overlays where the hub side requires a manually defined tunnel IP address, and the spoke can be flexibly configured, including interoperability with third-party IPsec devices. As described in the Fortinet SD-WAN Architect Guide: “For some overlays, the tunnel interface IP is configured statically on the hub side, which allows more control over overlay subnetting and facilitates the use of user-defined overlay IP addresses. This approach is also a requirement for compatibility with non-FortiGate endpoints, such as third-party IPsec devices that may not support dynamic address assignment via IKE or proprietary mechanisms.” This enables hybrid SD-WAN environments and advanced designs involving external partners or cloud services. Overlay IP flexibility is critical for route control and segmentation.

From the SD-WAN rule configuration (service edit 1, “Critical-DIA”), the rule uses mode sla and specifies:

set priority-members 1 2

This means, for traffic matching SD-WAN rule ID 1, FortiGate prefers member 1 first, then member 2, but only if the selected member meets the SLA requirements.

From the SD-WAN event log, the message explicitly states:

Member status changed. Member out-of-sla.

The log includes Member: 1

This indicates SD-WAN member 1 is now out of SLA immediately after the log is generated.

From the SD-WAN member status output:

Member(1) corresponds to interface port1

Member(2) corresponds to interface port2

Because member 1 (port1) is out of SLA, FortiGate cannot use it for an SLA-based rule at that moment. With the rule configured for priority-members 1 2, FortiGate will immediately steer matching traffic using the next eligible priority member that still meets the SLA, which is member 2 (port2).

Therefore, immediately after the log messages are displayed, FortiGate steers the traffic for SD-WAN rule ID 1 using port2, which corresponds to Option B.

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Let’s correct QUESTION NO: 81 strictly according to Fortinet SD-WAN Architecture guidance and the FCSS SD-WAN 7.6 design principles.

Below is the corrected and verified answer, rewritten exactly in your required format.

The log messages shown in the exhibit include the following key indicators:

processing notify type SHORTCUT_QUERY

shortcut-query received from 192.2.0.1

local-nat=yes, peer-nat=no

NAT hole punching for peer at 192.2.0.1:4500

In the FCSS SD-WAN 7.6 ADVPN workflow, shortcut queries are always initiated by spokes, not hubs. A spoke sends a shortcut query to its hub when it detects traffic destined for another spoke. The hub’s role is to receive this shortcut query and forward the discovery information toward the destination spoke, enabling the two spokes to build a direct shortcut tunnel.

The device name in the log (HUB1-VPN1) and the presence of NAT hole punching coordination clearly indicate that this device is acting as a hub, not a spoke. Hubs do not form shortcuts themselves; instead, they facilitate shortcut establishment between spokes by relaying discovery and negotiation information.

Option A is incorrect because a spoke does not receive shortcut queries from other spokes directly.

Option B is incorrect because the log does not indicate that the shortcut has already been established; it shows the query and coordination phase, not completion.

Option D is incorrect because hubs do not initiate shortcut queries toward spokes.

Therefore, the correct description is that this device is a hub that has received a shortcut query from a spoke and has forwarded it to another spoke, which corresponds to option C.

In an SD-WAN rule, you can steer application traffic by using Internet Service Database (ISDB) entries. Facebook and LinkedIn are predefined ISDB objects in FortiGate, so the correct way is to select them in the Internet service field under Destination. This ensures that all traffic to these applications is matched and routed through the chosen (less costly) link.

From the SD-WAN service configuration, rule edit 3 (name "Corp") is configured with:

set mode sla

set load-balance enable

set dst "Corp-net"

set src "LAN-net"

SLA checks referenced under config sla

Traffic from 10.0.1.101 to 10.0.0.126 matches this rule because the destination is within the corporate network range (shown in the policy-route/proute output as destination 10.0.0.0–10.255.255.255 for the Corp service).

In the diagnose firewall proute list output for vwl_service=3 (Corp), FortiGate shows which SD-WAN members are eligible based on SLA pass results:

oif=21 (HUB1-VPN3) num_pass=2

oif=20 (HUB1-VPN2) num_pass=0

oif=19 (HUB1-VPN1) num_pass=0

This indicates that, for the SLA-based rule, only HUB1-VPN3 is meeting the SLA requirements (it is the only member with num_pass=2). The other members have num_pass=0, so they are not eligible for forwarding under this SLA rule even though links are up.

The sniffer trace further corroborates the forwarding decision by showing the traffic egressing through HUB1-VPN3.

Therefore, FortiGate will steer the HTTP traffic through only HUB1-VPN3, which corresponds to Option A.

For a large-scale SD-WAN deployment (such as 1000 spokes) where ADVPN shortcut routing is required and some remote sites connect via FortiSASE, the recommended overlay routing configuration is BGP running on loopback interfaces, combined with dynamic BGP for ADVPN shortcut routing. This design leverages the scalability and resilience of BGP, allowing dynamic discovery and route exchange necessary for shortcut tunnels between spokes in ADVPN environments. Using loopback interfaces for BGP peering is considered best practice because it decouples routing protocol stability from physical link status, ensuring that if a physical underlay interface fails, the BGP session remains up as long as there’s an alternate path. With dynamic BGP, each spoke can efficiently learn the routes to other spokes and dynamically establish shortcuts, which is critical at this scale. This method also integrates smoothly with FortiSASE for remote connectivity to the SD-WAN hub, providing flexibility and centralized management.