FCSS_SDW_AR-7.6 FCSS - SD-WAN 7.6 Architect Questions and Answers

By default, local-out traffic does not use SD-WAN → FortiGate normally sends local-out traffic (e.g., DNS, NTP, FortiGuard updates) directly through its interfaces without applying SD-WAN rules.

You must configure each local-out feature individually to use SD-WAN → To steer local-out traffic via SD-WAN, you must explicitly configure the desired local-out features (e.g., DNS, FortiGuard, CAPWAP) to use SD-WAN rules.

When SD-WAN load balancing is required with link quality awareness, FortiOS relies on SLA-based strategies. These strategies evaluate link performance using performance SLAs (latency, jitter, packet loss, MOS) and then make forwarding decisions accordingly.

Option A is correct.

In FortiOS 7.6, when an SLA-based SD-WAN rule has load balancing enabled, FortiGate distributes traffic only across the members that meet the SLA targets. Any member that is out of SLA is excluded from load balancing. This behavior ensures that traffic is not forwarded over degraded links while still allowing load distribution across healthy paths.

Option C is correct.

The lowest cost (SLA) strategy is an SLA-based strategy that considers link quality while also allowing SD-WAN load balancing. When multiple members meet the SLA requirements and have equal cost, FortiGate can load balance traffic across them using the configured hash mode. This makes the lowest cost SLA strategy suitable when both link quality and load balancing are required.

Why the other options are incorrect:

Option B is incorrect because the best quality strategy is designed to select the single best-performing link based on SLA metrics. It does not support SD-WAN load balancing across multiple links.

Option D is incorrect because the best quality strategy does not support load balancing at all, so the statement about round-robin hash mode is invalid.

Therefore, the two correct facts to consider are A and C.

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.

Policy 3 points traffic To = HUB1-VPN1, which is an SD-WAN member interface. In SD-WAN you must reference the SD-WAN zone (the logical interface) in policies, not its member tunnels. Change the policy’s To interface to the zone HUB1, and the install will succeed.

From the exhibit, both branches have an SD-WAN zone named overlay with set advpn-select enable, and each SD-WAN member in that zone is assigned a transport-group value.

Branch-A members:

T1 → transport-group 1

T2 → transport-group 1

T3 → transport-group 2

Branch-B members:

TA → transport-group 1

TB → transport-group 2

TC → transport-group 3

In FCSS SD-WAN 7.6 ADVPN design, transport-group is used to constrain which underlays are allowed to form ADVPN shortcuts with each other. A spoke can establish an ADVPN shortcut only between interfaces that belong to the same transport-group on both sides. This prevents building shortcuts across dissimilar transports.

Evaluating the options:

Option D (T2 on Branch-A with transport-group 1 and TA on Branch-B with transport-group 1) is a valid shortcut pairing.

Option C is not valid because T3 is transport-group 2 while TC is transport-group 3, so they are not permitted to form a shortcut.

Option A is incorrect because not all overlay-zone interfaces are eligible; eligibility is restricted by transport-group matching.

Option B is incorrect because ADVPN shortcuts are spoke-to-spoke tunnels (facilitated by the hub), not limited to “interfaces connected to hub only.”

Therefore, the valid shortcut pairing listed is between T2 on Branch-A and TA on Branch-B, which corresponds to Option D.

Your requirements map to two key MSSP goals described in the FCSS SD-WAN 7.6 blueprint patterns:

Delegate as much administration and management as possible to the MSSPThis is best achieved when the hub security and SD-WAN control point is located on the MSSP premises, because the MSSP can centrally operate the core enforcement and overlay control. Both option B (dedicated hub at MSSP) and option D (shared hub at MSSP with customer isolation) meet this requirement.

Each site must maintain direct internet access (DIA) and be secure, with significant site-to-site trafficIn Fortinet SD-WAN MSSP designs, spokes can still use local breakout for DIA while also building secure overlays for inter-site traffic. Placing the hub at the MSSP enables centralized security services and scalable inter-site connectivity management while preserving DIA where required. Options B and D support this operating model.

Why the other options do not best match:

A includes a dedicated hub on the customer premises, which reduces how much the MSSP can centralize and operate from its own environment, so it does not maximize delegation.

C places both hub and spokes on the customer premises. While the MSSP can manage using a dedicated ADOM, this blueprint does not align as strongly with “delegate installation and management” to the MSSP as the designs where the hub is hosted and operated from the MSSP premises.

Therefore, the two MSSP deployment blueprints that address your requirements are B and D.

This is because the setting minimum-sla-meet-members = 2 requires at least two SD-WAN zone members (in this case, HUB2-VPN1, HUB2-VPN2, and HUB2-VPN3) to pass the defined SLA health check (HUB1_HC) before the FortiGate will establish ADVPN shortcuts. If fewer than two members meet the SLA, shortcuts will not be created.

One SD-WAN rule is defined with application categories as the destination → The diagnose output shows application control matches such as Microsoft.Portal, Operational.Technology, and Social.Media, confirming that SD-WAN rules are using application categories as destinations.

UDP traffic destined to the subnet 10.22.0.0/24 matches a policy route → The first entry (id=1) shows protocol=17 (UDP) with destination 10.22.0.0/24, confirming this traffic is handled by a policy route instead of an SD-WAN rule.

With the Best Quality strategy, FortiGate first checks which links meet the SLA targets defined in the selected performance SLA (in this case, Custom-profile-1). Among those qualified links, FortiGate then uses the member configuration order to decide preference. If multiple links still qualify, it finally considers the member local cost to select the best path.

The rule is in SLA mode with two SLAs. From the status, HUB1-VPN2 and HUB1-VPN3 meet the SLA (sla(0x2) and sla(0x3)), while HUB1-VPN1 does not (sla(0x0)). Among members that meet SLA, FortiGate uses the configured order (priority-members 4 5 6) to pick the first eligible one—HUB1-VPN2—so traffic is routed over HUB1-VPN2.

In the exhibit, the IPsec tunnel statistics event log entries include the field advpnsc.

Fortinet documents that advpnsc identifies whether the VPN event is based on an ADVPN shortcut:

advpnsc=1 → the tunnel is an ADVPN shortcut

advpnsc=0 → not an ADVPN shortcut (Fortinet Documentation Library)

In the shown logs, the tunnel vpntunnel="HUB1-VPN1_0" has advpnsc=1, which means HUB1-VPN1_0 is an ADVPN shortcut tunnel. (Fortinet Documentation Library)

The other tunnels shown (for example VPN4_0 and HUB2-VPN3) have advpnsc=0, which only indicates no shortcut is identified for those log entries—it does not prove they “cannot accept” shortcuts, only that the specific event is not a shortcut. (Fortinet Documentation Library)

The policy-route output shows the matching SD-WAN service for destination 10.66.0.0/24 is vwl_service=4 (LAN-to-Corp2) with vwl_mbr_seq=1 2 and paths oif=3(port1) and oif=4(port2). Therefore, traffic from 10.0.1.133 to 10.66.0.125 is steered via SD-WAN member ID 1 or 2.

The line sdwan_mbr_seq=1 sdwan_service_id=4 indicates that this session is part of an SD-WAN rule. sdwan_service_id=4 confirms that the session is being handled by SD-WAN rule ID 4. This directly links the flow to the SD-WAN configuration.

The line no_offload_reason: redir-to-ips denied-by-nturbo shows that the session is not offloaded to the NPU (Network Processing Unit) and is being processed by the main CPU. A session that is not offloaded can be re-evaluated. If the outgoing interface (the one currently being used) goes down, the FortiGate will re-evaluate the session against the SD-WAN rules to find a new active member to steer the traffic through. This is a fundamental behavior of SD-WAN, which ensures network resilience.

In FortiOS 7.6, when SD-WAN is enabled, physical and logical WAN interfaces are added as SD-WAN members and are abstracted behind the SD-WAN interface (virtual-wan-link or SD-WAN zone). Traffic forwarding decisions are then made by SD-WAN rules instead of individual interfaces.

As documented in the FCSS SD-WAN 7.6 curriculum and Fortinet SD-WAN architecture guides, firewall policies must reference the SD-WAN interface or SD-WAN zone, not the individual WAN interfaces that are members of SD-WAN. Therefore, during the configuration update process, existing firewall policies that reference physical WAN interfaces must be updated to reference the SD-WAN interface.

Option A is incorrect because routing configuration does not require replacing interface references when SD-WAN is enabled. Static and dynamic routes typically point to the SD-WAN interface automatically, and SD-WAN rules handle path selection.

Option B is incorrect because SD-WAN is a built-in FortiOS feature. It does not require a separate license and does not require a reboot when enabled.

Option D is incorrect because interfaces must remain enabled to function as SD-WAN members. Disabling an interface would prevent SD-WAN from using it for traffic forwarding.

Therefore, the required action during the SD-WAN configuration update process is to replace references to interfaces used as SD-WAN members in the firewall policies, which corresponds to option C.

In FortiOS 7.6, static routes can reference either:

an SD-WAN zone (for example, virtual-wan-link or a user-defined SD-WAN zone), or

a specific SD-WAN member interface that belongs to that zone.

However, FortiOS enforces a routing constraint to avoid ambiguity during route resolution. Two static routes cannot have the same destination prefix if one points to an SD-WAN zone and the other points to an SD-WAN member within that zone. This would create an overlapping and conflicting forwarding decision.

Therefore, if you configure:

one static route that references an SD-WAN zone, and

another static route that references an SD-WAN member belonging to that same zone,

the destination subnets of the two static routes must be different.

Why the other options are incorrect:

Option A is incorrect because FortiOS does allow static routes that reference individual SD-WAN members.

Option B is incorrect because static routes can reference SD-WAN zones.

Option D is incorrect because static routing decisions in FortiOS are based on destination prefixes, not source prefixes.

Thus, the correct answer is C.

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.

The FCSS SD-WAN 7.6 curriculum describes multiple standard SD-WAN deployment designs, each mapped to a specific operational goal or constraint.

A cloud on-ramp topology is designed to optimize connectivity to cloud services such as SaaS and IaaS. This design provides the most efficient and reliable path to cloud applications by establishing direct tunnels to cloud gateways or cloud workloads and by avoiding backhauling traffic through a central data center. As a result, its primary indication is improving the performance of cloud applications, which makes option A correct.

A remote breakout (centralized breakout) design forwards all internet-bound traffic from branch sites to a central hub for security inspection. This allows security policies, inspection, and logging to be centralized on a high-capacity FortiGate at the hub. Because branch devices do not need advanced local security configurations, this design also limits local management requirements, which makes option C correct.

Option B is incorrect because a standalone SD-WAN design is not selected simply because a site has only one WAN link. SD-WAN provides its main benefits when multiple WAN paths exist, and single-link sites do not gain meaningful traffic-steering advantages.

Option D is incorrect because a direct internet access (DIA) design performs local internet breakout at the branch and therefore requires strong local security capabilities. DIA does not inherently increase traffic security and is not intended for devices with limited capabilities.

Therefore, the two correct associations are A and C.

The diagnose output lists SD-WAN members 4(HUB1-VPN1), 5(HUB1-VPN2), 7(HUB2-VPN1), 8(HUB2-VPN2), and 9(HUB2-VPN3). It does not include member 6 (HUB1-VPN3). From the template, HUB1-VPN3 is installed only on branch2_fgt and branch3_fgt - not on branch1_fgt. Therefore, the output must be from branch1_fgt.