F5CAB5 Exam Dumps : BIG-IP Administration Support and Troubleshooting (F5CAB5) exam

In an HTTPS session, the application-layer payload—including HTTP request headers, response headers, cookies, and body content—is encrypted using SSL/TLS. Without decrypting the traffic (for example, without SSL offloading on BIG-IP or access to the private keys), a packet capture cannot reveal any HTTP-level details.

However,network-layer and transport-layer information remains visible, even when encryption is used. This includes source and destination IP addresses, source and destination ports, TCP flags, sequence numbers, and TLS handshake metadata. Therefore, thesource IP address (Option B)is visible in a packet capture of HTTPS traffic without decryption.

Options A, C, and D are incorrect because HTTP headers and cookies are part of the encrypted payload once HTTPS is established. BIG-IP troubleshooting documentation emphasizes this distinction when analyzing encrypted traffic flows using tcpdump, as administrators must rely on IP, port, and timing information unless SSL inspection or decryption is configured.

The BIG-IP system uses the audit log to track administrative actions and configuration changes.

Audit Logging Functionality: When a user modifies the configuration via the Configuration Utility (GUI), the Traffic Management Shell (tmsh), or iControl, the system records the event in the audit log. This includes the name of the user who made the change, the timestamp, and the specific command or object that was modified.

Log Location: The audit log is stored at /var/log/audit.

Evaluation of Other Options:

/var/log/messages (Option A) contains general system and kernel messages but is not the primary source for configuration change details.

/var/log/secure (Option B) primarily logs authentication and authorization attempts (logins and logouts).

/var/log/user.log (Option D) is a generic Linux log file for user-level applications and does not track BIG-IP LTM configuration changes.

The key clue in the exhibit is the pool member’s availability showing“Offline (Enabled) – Parent down”. In BIG-IP terminology, a pool member inherits the status of itsparent node. If thenodeis marked down (for example, by a node-level monitor or a default “node is down” condition), thenall pool members using that node IPwill also be marked down and will not receive any traffic, even if the application service on the member port might be healthy.

While the HTTPS monitor configuration (send/receive strings) is displayed, the statusspecificallyindicates anode (parent) failure, not a service-level failure. If the problem were the application not matching the receive string, you would typically see the member down due to themember’s monitorfailing (and the status would reflect monitor failure details), rather than “parent down.”

Option D is too broad; BIG-IP can generally reach the subnet (other servers work), and this symptom points to a specific node condition. Option C is incorrect because HTTP/1.1 is commonly used for monitoring and is valid when properly formatted (especially with a Host header). Therefore, the most likely cause is that thenode health monitor is not responding, causing the node—and consequently the member—to be marked down.