Cisco 300-710 - Securing Networks with Cisco Firewalls

If a task to generate troubleshooting files in Cisco Secure Firewall Management Center (FMC) is completed successfully but removed before the files are downloaded, the following steps can be taken to determine the filename and obtain the generated troubleshooting files without regenerating them:

Go to expert mode on Secure FMC:

Access expert mode on the FMC via SSH or the console.

List the contents of the directory/var/commonto locate the generated troubleshooting files. Use the commandls /var/common.

Use the System Monitoring Audit logs:

In FMC, navigate toSystem > Monitoring > Audit.

Find the line containing the " Generate Troubleshooting Files " string to determine the correct filename.

These actions help identify and retrieve the generated troubleshooting files without the need to regenerate them, saving time and resources.

When configuring a new report template based on a saved search in Cisco Secure Firewall Management Center (FMC), it is important to note that saved searches are specific to the report template they were created with. Saved searches cannot be freely used across different report templates.

To use a different type of saved search, you must ensure that it aligns with the specific report template being used. This restriction ensures that the saved search parameters match the report ' s data requirements.

To ensure that router R2 removes the directly connected route for 192.168.1.0/24 from its routing table when the cable between router R1 and the Secure FTD device is disconnected, the network engineer must implement the " Propagate Link State " option on the Secure FTD device. This option allows the FTD to propagate the link state changes to adjacent devices, ensuring that the disconnection is recognized and the routing table is updated accordingly.

Steps:

Access the FTD device configuration via FMC.

Navigate to the interface settings for the relevant interfaces.

Enable the " Propagate Link State " option for the interfaces connected to R1 and R2.

Deploy the changes to the FTD device.

This configuration ensures that the link state changes are communicated to router R2, prompting it to remove the disconnected route from its routing table.

The Capture w/Trace wizard in Cisco FMC allows you to capture packets on an FTD device and trace their path through the Snort engine. This can help you troubleshoot connectivity issues from an endpoint behind an FTD device and a public DNS server, as well as verify the Snort verdict for the DNS traffic. The Capture w/Trace wizard lets you specify the source and destination IP addresses, ports, and protocols for the packets you want to capture and trace, as well as the FTD device and interface where you want to perform the capture. You can also apply filters to limit the capture size and duration. After you start the capture, you can ping the DNS server from the endpoint and then view the captured packets and their Snort verdicts in the FMC web interface2.

To use the Capture w/Trace wizard in Cisco FMC, you need to follow these steps2:

In the FMC web interface, navigate to Troubleshooting > Capture/Trace.

Click New Capture.

Choose an FTD device from the Device drop-down list.

Choose an interface from the Interface drop-down list.

Enter the source and destination IP addresses, ports, and protocols for the packets you want to capture and trace. For example, if you want to capture DNS queries from an endpoint with IP address 10.1.1.100 to a DNS server with IP address 8.8.8.8, you can enter these values:

Source IP: 10.1.1.100

Source Port: any

Destination IP: 8.8.8.8

Destination Port: 53

Protocol: UDP

Optionally, apply filters to limit the capture size and duration. For example, you can set the maximum number of packets to capture, the maximum capture file size, or the maximum capture time.

Click Start.

Ping the DNS server from the endpoint and wait for some packets to be captured.

Click Stop to stop the capture.

Click View Capture to see the captured packets and their Snort verdicts.

The other options are incorrect because:

Performing a Snort engine capture using tcpdump from the FTD CLI will not allow you to trace the path of the packets through the Snort engine or verify their Snort verdicts. Tcpdump is a command-line tool that can capture packets on an FTD device, but it does not provide any information about how Snort processes those packets or what actions Snort takes on them2.

Creating a Custom Workflow in Cisco FMC will not help you troubleshoot a connectivity issue from an endpoint behind an FTD device and a public DNS server. A Custom Workflow is a user-defined set of pages that display event data in different formats, such as tables, charts, maps, and so on. A Custom Workflow does not allow you to capture or trace packets on an FTD device3.

Running the system support firewall-engine-debug command from the FTD CLI will not allow you to simulate real DNS traffic on the FTD device or verify the Snort verdict for that traffic. The firewall-engine-debug command is a diagnostic tool that can generate synthetic packets and send them through the Snort engine on an FTD device. The synthetic packets are not real network traffic and do not affect any connections or policies on the FTD device4.

Transparent mode is a firewall configuration in which the firewall acts as a “bump in the wire” or a “stealth firewall” and is not seen as a router hop to connected devices. In transparent mode, the firewall can forward traffic at both layer 2 and layer 3 for the same subnet, as it does not perform any address translation or routing. The firewall inspects the traffic and applies security policies based on the source and destination IP addresses, ports, and protocols. Transparent mode is useful when you want to deploy a firewall without changing the existing network topology or addressing scheme1.

To determine if a host is infected with malware, the network administrator can look at the Indications of Compromise (IOC) feature in Cisco FMC. The IOC feature analyzes network and endpoint data collected by Firepower sensors and AMP for Endpoints connectors, and identifies hosts that exhibit signs of compromise or infection. The IOC feature uses predefined rules based on Cisco Talos intelligence and other sources to detect IOCs on hosts. One of these rules is CnC Connected, which indicates that a host has communicated with a command-and-control (CnC) server that is known to be associated with malware activity2.

To view the IOC information for a host, the network administrator can navigate to Analysis > Hosts > Indications of Compromise in Cisco FMC, and select a host from the table. The IOC Details page will show the IOC events for that host, including the CnC Connected event, along with other information such as severity, timestamp, source, destination, protocol, and rule name. The network administrator can also view more details about each IOC event by clicking on it2.

The other options are incorrect because:

Analysis > Files > Malware Events shows information about files that have been detected as malware by Firepower sensors or AMP for Endpoints connectors. This does not show information about hosts that are infected with malware or have communicated with CnC servers3.

Analysis > Hosts > Host Attributes shows information about hosts that have been discovered by Firepower sensors, such as IP address, MAC address, operating system, applications, users, vulnerabilities, and so on. This does not show information about IOCs or CnC connections on hosts4.

Analysis > Files > Network File Trajectory shows information about files that have traversed your network and have been detected by Firepower sensors or AMP for Endpoints connectors. This allows you to track where a file came from, where it went, and what happened to it along the way. This does not show information about hosts that are infected with malware or have communicated with CnC servers5.