FCSS_EFW_AD-7.6 Sample Questions Answers

Use metadata variables to dynamically assign values according to each FortiGate device:

Metadata variables in FortiManager allow device-specific configurations to be dynamically assigned without manually configuring each FortiGate. This is especially useful when deploying multiple devices with similar base configurations.

Use provisioning templates and install configuration settings at the device layer:

Provisioning templates in FortiManager provide a structured way to configure FortiGate devices. These templates can define interfaces, policies, and settings, ensuring that each device is correctly configured upon deployment.

Add FortiGate devices on FortiManager as model devices, and use ZTP or LTP to connect to FortiGate devices:

Zero-Touch Provisioning (ZTP) and Local Touch Provisioning (LTP) help automate the deployment of FortiGate devices. By adding devices as model devices in FortiManager, configurations can be pushed automatically when devices connect for the first time, reducing manual effort.

To minimize CPU and RAM usage while still enforcing security features like web filtering and application control, SSL certificate inspection mode is the best choice.

● SSL certificate inspection allows FortiGate to inspect only the SSL/TLS handshake, including the Server Name Indication (SNI) and certificate details, without decrypting the full encrypted payload.

● This enables features like web filtering and application control because FortiGate can determine the destination website or application based on SNI and certificate information.

● It significantly reduces system load compared to full SSL inspection, which requires full decryption and re-encryption of traffic.

FortiGate devices with NP6 (Network Processor 6) acceleration offload traffic directly to hardware, bypassing the CPU for improved performance. When auto-asic-offload is enabled in a firewall policy, most of the traffic does not reach the CPU, which means it won't be captured by the standard sniffer trace command.

Since NP6-accelerated traffic is handled entirely in hardware, only a small portion of initial packets (such as session setup packets or exceptions) might be seen in the sniffer output. To capture all packets, the administrator must disable hardware offloading using:

config firewall policy

edit

set auto-asic-offload disable

end

Disabling ASIC offload forces traffic to be processed by the CPU, allowing the sniffer tool to capture all packets.

The Fortinet FGSP (FortiGate Session Life Support Protocol) cluster allows session synchronization between two FortiGate devices to provide seamless failover. However, ICMP (ping) is a connectionless protocol, and by default, FortiGate does not synchronize connectionless sessions unless explicitly enabled.

In the exhibit:

● The command get system session list | grep icmp on FortiGate_B returns no output, meaning that ICMP sessions are not being synchronized from FortiGate_A.

● If session-pickup-connectionless is disabled, FortiGate_B will not receive ICMP sessions, causing packet loss during failover.

IKEv2 (Internet Key Exchange version 2) is an improvement over IKEv1, offering enhanced security, efficiency, and flexibility in VPN configurations.

It includes stronger Diffie-Hellman (DH) groups, such as Elliptic Curve (ECP) groups.

IKEv2 supports stronger cryptographic algorithms, including Elliptic Curve Diffie-Hellman (ECDH) groups such as ECP256 and ECP384, providing improved security compared to IKEv1.

It supports the extensible authentication protocol (EAP).

IKEv2 natively supports EAP authentication, which allows integration with external authentication mechanisms such as RADIUS, certificates, and smart cards. This is particularly useful for remote access VPNs where user authentication must be flexible and secure.

Applying an aggressive IPS profile without prior testing can disrupt legitimate applications by incorrectly identifying normal traffic as malicious. To prevent disruptions while still monitoring for threats:

● Enable IPS in "Monitor Mode" first:

● This allows FortiGate to log and analyze potential threats without actively blocking traffic.

● Administrators can review logs and fine-tune IPS signatures to minimize false positives before switching to blocking mode.

● Verify and adjust signature patterns:

● Some signatures might trigger unnecessary blocks for legitimate application traffic.

● By analyzing logs, administrators can disable or modify specific rules causing false positives.

The set tcp-mss-sender and set tcp-mss-receiver commands in a firewall policy allow an administrator to adjust the Maximum Segment Size (MSS) of TCP packets.

This setting controls the largest payload size that a device can handle in a single TCP segment, ensuring that packets do not exceed the allowed MTU (Maximum Transmission Unit) along the network path.

● set tcp-mss-sender adjusts the MSS value for outgoing TCP traffic.

● set tcp-mss-receiver adjusts the MSS value for incoming TCP traffic.

This helps prevent issues with fragmentation and MTU mismatches, improving network performance and avoiding retransmissions.

In an IBGP (Internal BGP) network, all routers must be fully meshed, meaning every router must establish a BGP session with every other router in the same autonomous system (AS). This does not scale well in large networks due to the exponential increase in BGP sessions.

To optimize and scale IBGP, Route Reflectors (RRs) are used. A Route Reflector (RR) reduces the number of IBGP peer connections by allowing a centralized router (RR) to redistribute IBGP routes to other IBGP peers (called clients). This eliminates the need for a full mesh, significantly reducing BGP session overhead.

By configuring the route-reflector-client setting on IBGP peers, an administrator can:

● Scale IBGP sessions by reducing the number of direct BGP peer connections.

● Optimize the routing table by ensuring routes are efficiently propagated within the IBGP network.

● Eliminate the need for full mesh topology, making IBGP more manageable.

When multiple remote sites connect to the same hub using overlapping subnets, FortiGate needs to determine which route should be used for traffic forwarding. The route-overlap setting in IPsec Phase 2 allows FortiGate to handle this scenario by deciding whether to keep the existing route (use-old) or replace it with a new route (use-new).

In an ECMP (Equal-Cost Multi-Path) routing setup, both routes should be retained and balanced, but FortiGate does not support ECMP directly over overlapping routes in IPsec Phase 2. Instead, an administrator must decide which connection takes precedence using route-overlap settings.

Unlike IPS or antivirus databases, FortiGate does not store a full web filter database locally. Instead, FortiGate queries FortiGuard (or FortiManager, if configured) dynamically to classify and filter web content in real time.

Key points:

● Web filtering works on a cloud-based model:

● When a user requests a website, FortiGate queries FortiGuard servers to check its category and reputation.

● The response is then cached locally for faster lookups on repeated requests.

● No local web filter database version:

● Unlike IPS and antivirus, which download and store signature updates locally, web filtering relies on cloud-based queries.

● This is why no database version appears in the GUI.

● Flow mode vs Proxy mode:

● In proxy mode, FortiGate can cache some web filter data, improving performance.

● In flow mode, all queries happen dynamically, with no locally stored database.

When FortiGate is operating in proxy mode with full SSL inspection enabled, it inspects encrypted HTTPS traffic by default on port 443. However, some websites may use non-standard HTTPS ports (such as 8443), which FortiGate does not inspect unless explicitly configured.

To ensure that FortiGate inspects HTTPS traffic on port 8443, administrators must manually add port 8443 in the Protocol Port Mapping section of the SSL/SSH Inspection Profile. This allows FortiGate to treat HTTPS traffic on port 8443 the same as traffic on port 443, enabling proper inspection and enforcement of FortiGuard category-based web filtering.

FortiGate, like other security appliances, cannot analyze encrypted HTTPS traffic unless it decrypts it first. If only certificate inspection is enabled, FortiGate can see the certificate details (such as the domain and issuer) but cannot inspect the actual web content.

To fully analyze the traffic and detect potential malware threats:

● Full SSL inspection (Deep Packet Inspection) must be enabled in the SSL/SSH Inspection Profile.

● This allows FortiGate to decrypt the HTTPS traffic, inspect the content, and then re-encrypt it before forwarding it to the user.

● Without full SSL inspection, threats embedded in encrypted traffic may go undetected.

When standardizing the deployment of FortiGate devices across branches using FortiManager, the best practice is to use metadata variables. This allows for dynamic interface configuration while maintaining a single, consistent policy package for all branches.

● Metadata variables in FortiManager enable interface roles and configurations to be dynamically assigned based on the specific FortiGate device.

● This ensures scalability and consistent security policy enforcement across all branches without manually adjusting interface settings for each device.

● When a new branch FortiGate is deployed, metadata variables automatically map to the correct physical interfaces, reducing manual configuration errors.

When configuring ADVPN (Auto-Discovery VPN) to connect overlay networks across different hubs using IBGP and EBGP, special configurations are required to allow spokes from different overlay networks to dynamically establish tunnels.

● set auto-discovery-crossover enable

● This allows cross-hub tunnel discovery in an ADVPN deployment where multiple hubs are used.

● Since Hub A and Hub B belong to different overlays, enabling crossover discovery ensures that spokes from one overlay can dynamically create direct tunnels to spokes in the other overlay when needed.

● set enforce-multihop enable

● This setting ensures that BGP peers using loopback interfaces can establish connectivity even if they are not directly connected.

● Multihop BGP sessions are required when using loopback addresses as BGP peer sources because the connection might need to traverse multiple routers before reaching the BGP neighbor.

● This is especially useful in ADVPN deployments with multiple hubs, where routes might need to cross from one hub to another.