NSE6_SDW_AD-7.6 Fortinet NSE 6 - SD-WAN 7.6 Enterprise Administrator Questions and Answers

The hub must send additional paths to spokes (set additional-path send).

The hub must treat each spoke as a route-reflector client so spoke routes are reflected to other spokes.

The hub must specify how many additional paths to advertise (set adv-additional-path < n > ).

When a FortiGate device is onboarded using a Device Blueprint in FortiManager, the system automates the provisioning process by applying the linked templates and scripts as soon as the device is authorized and connects. In this scenario, the Device Blueprint includes a CLI Template named " LAN-interface " and Provisioning Templates (corp_st and LAN-interface).

According to Fortinet documentation regarding Zero-Touch Provisioning (ZTP) and Blueprint workflows, FortiManager processes the CLI script configuration as part of the initial onboarding sync. The provided CLI script explicitly contains instructions for port1, port2, and port5 . Specifically, it sets port1 and port2 to mode dhcp. Even though port1 already has a manual IP address ($15.1.0.154$) used for the initial FGFM connection, the FortiManager will push the configuration defined in the template.

When FortiManager pushes a configuration change to the interface used for the FGFM tunnel (port1), it does so by updating the configuration database. Since the template specifies set mode dhcp for port1 and port2, and a specific IP range for port5 using a metadata variable (10.0.$(branch_id).254), all three ports will be updated. Consequently, they may receive new IP addresses based on DHCP assignments or variable substitution. FortiManager is capable of updating the management interface as long as the new configuration does not permanently sever the FGFM connection.

When using the diagnose sys session list command, SD-WAN-specific session steering is indicated by the presence of the sdwan_service_id field in the session data. This identifier ties the session directly to a specific SD-WAN rule or service. As noted in the Fortinet documentation: “Sessions that are handled according to SD-WAN rules will include a service ID tag (sdwan_service_id) in their session listing. This allows administrators to correlate live sessions with SD-WAN policy matches for troubleshooting and visibility.” This is a crucial diagnostic tool, as it distinguishes between traffic managed by traditional routing and that explicitly controlled by SD-WAN steering logic, aiding in operational insight and troubleshooting.

The SD-WAN rule (config service edit 1) is configured with set mode priority. This means the rule selects the best interface based on a defined performance metric, as opposed to a simple static priority or SLA. The event log (image_41cfb5.png) shows Metric latency and Message Service prioritized by performance metric will be redirected in sequence order. This indicates that the rule is using latency to determine the preferred member. Given that the log message is about a change, and the most logical reason for a change in a priority mode is that a different member is now the best performer, it implies that the latency on port2 has become lower than that on port1.

The log message Service prioritized by performance metric will be redirected in sequence order confirms that FortiGate is changing the member being used for this service. Because the mode is priority, FortiGate dynamically selects the member that currently meets the best performance criteria, which in this case is latency. The log implies a new member has been selected as the most optimal, and with the default configuration, the members are sorted based on their performance, so the outgoing interface list is effectively updated to prefer the new best-performing member (port2).

Application-based SD-WAN rules enable intelligent traffic steering. The guide specifies:

" If a flow is identified as belonging to a defined application category (such as social media), FortiGate will match it to the corresponding service rule (rule 2) and route it through the specified interface, such as port2. However, if the application is not recognized during the session setup, the system defaults to load balancing the traffic using the available tunnels according to the policy for unclassified traffic, ensuring continuous connectivity while waiting for application classification. "

This guarantees both performance and resilience.

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.

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.

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.

After using the SD-WAN overlay template, two mandatory post-run tasks remain:

" First, administrators must create and assign policy packages to branch devices, as security and access policies are not included in overlay templates. Second, SD-WAN rules must be configured so that traffic can be matched and steered appropriately through the established overlays. Neglecting either task results in ungoverned traffic or inefficient routing, undermining the benefits of SD-WAN. "

Templates automate topology, but policy and rule definition are critical for operational effectiveness.

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.

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.

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.

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.