BIG-IP Administration Support and Troubleshooting (F5CAB5) exam Version: Demo [ Total Questions: 10] Web: www.certsout.com Email: support@certsout.com F5 F5CAB5 IMPORTANT NOTICE Feedback We have developed quality product and state-of-art service to ensure our customers interest. If you have any suggestions, please feel free to contact us at feedback@certsout.com Support If you have any questions about our product, please provide the following items: exam code screenshot of the question login id/email please contact us at and our technical experts will provide support within 24 hours. support@certsout.com Copyright The product of each order has its own encryption code, so you should use it independently. Any unauthorized changes will inflict legal punishment. We reserve the right of final explanation for this statement. F5 - F5CAB5 Certs Exam 1 of 8 Pass with Valid Exam Questions Pool A. B. C. D. A. B. Category Breakdown Category Number of Questions Given a scenario, review basic stats to confirm functionality 1 Identify network level performance issues 1 Identify the reason a virtual server is not working as expected 3 Identify the reason load balancing is not working as expected 3 Identify the reason a pool is not working as expected 2 TOTAL 10 Question #:1 - [Given a scenario, review basic stats to confirm functionality] A BIG-IP Administrator makes a configuration change to a Virtual Server on the Standby device of an HA pair. The HA pair is currently configured with Auto-Sync Enabled. What effect will the change have on the HA pair configuration? The change will be undone when Auto-Sync propagates the config to the HA pair. The change will be propagated next time a configuration change is made on the Active device. The change will be undone next time a configuration change is made on the Active device. The change will take effect when Auto-Sync propagates the config to the HA pair. Answer: D Explanation Understanding High Availability (HA) synchronization behavior is critical for maintaining a stable environment. In a device group where "Auto-Sync" is enabled, the BIG-IP system monitors the management plane for any configuration updates across all members. While best practices often suggest making changes on the "Active" device, TMOS allows changes on any device within the group. When a change is made on the "Standby" device, the system detects a configuration mismatch and, because Auto-Sync is enabled, it automatically pushes those changes to the other devices in the sync group, including the current Active member. To troubleshoot if this is working correctly, the administrator should review the "Sync Status" stats in the Configuration Utility. If the changes do not propagate, it suggests9 a breakdown i10n the HA trust relationship or network connectivity issues on the failover VLAN. Proper interpretation of this scenario confirms that the HA functionality is operating correctly, ensuring that both devices have a consistent set of virtual servers and pools, which is vital f11or seamless failover. Question #:2 - [Identify network level performance issues] Users report that traffic is negatively affected every time a BIG-IP device fails over. The traffic becomes stabilized after a few minutes. What should the BIG-IP Administrator do to reduce the impact of future failovers? Enable Failover Multicast Configuration F5 - F5CAB5 Certs Exam 2 of 8 Pass with Valid Exam Questions Pool B. C. D. Set up Failover Method to HA Order Configure MAC Masquerade Configure a global SNAT Listener Answer: C Explanation When traffic "stabilizes after a few minutes" following a failover, it points to a network-level performance issue involving ARP cache on upstream routers and switches. Each BIG-IP interface has a unique hardware MAC address. During failover, the Standby device takes over the floating IP address, but the upstream switch still associates that IP with the MAC of the now-offline device. Traffic is lost until the switch learns the new MAC or its ARP entry expires. "MAC Masquerading" solves this by creating a shared, virtual MAC address for the floating traffic group. This virtual MAC is used by whichever device is currently active. Because the MAC address for the virtual server IP never changes from the perspective of the network, the upstream devices do not need to update their ARP tables. This troubleshooting solution eliminates the delay associated with failover, providing a seamless transition and ensuring that application traffic flow is not disrupted when the BIG-IP HA state changes. Question #:3 - [Identify the reason a virtual server is not working as expected] A BIG-IP Administrator configured the following virtual server to pass traffic on all addresses and ports. After configuration is completed, the BIG-IP Administrator notices that the virtual server is unable to pass traffic. ltm virtual forwarding_any_vs { destination 0.0.0.0:any ip-forward mask 255.255.255.255 profiles { fastL4 { } } serverssl-use-sni disabled source 0.0.0.0/0 translate-address disabled translate-port disabled } F5 - F5CAB5 Certs Exam 3 of 8 Pass with Valid Exam Questions Pool A. B. C. A. B. C. D. Which part of the configuration is the cause of the issue? (Choose one answer) Incorrect destination configured Incorrect mask 255.255.255.255 Incorrect translate-address configured Answer: B Explanation This virtual server is intended to function as a , which is forwarding (IP-forwarding) virtual server commonly used for routing or firewall-style deployments where BIG-IP forwards traffic transparently without load balancing or address translation. For a forwarding virtual server to match and pass , the all traffic destination must be configured as 0.0.0.0:any , not 255.255.255.255. with a mask of 0.0.0.0 The configured mask 255.255.255.255 represents a , which restricts the virtual server to /32 host mask matching traffic destined only for the exact IP address 0.0.0.0. Since 0.0.0.0 is not a valid routable destination for normal traffic, no packets will ever match the virtual server, causing it to pass no traffic at all. This is a well-documented BIG-IP behavior: destination 0.0.0.0:any mask 0.0.0.0 together define a catch-all forwarding virtual server The destination itself (Option A) is correct for a forwarding VS, and disabling address translation (Option C) is expected and required for IP-forwarding mode. Therefore, the incorrect subnet mask is the sole reason the virtual server is not functioning as expected. Question #:4 - [Identify the reason load balancing is not working as expected] Due to a change in application requirements, a BIG-IP Administrator needs to modify the configuration of a Virtual Server to include a Fallback Persistence Profile. Which persistence profile type should the BIG-IP Administrator use for this purpose? SSL Hash Universal Source Address Affinity Answer: D F5 - F5CAB5 Certs Exam 4 of 8 Pass with Valid Exam Questions Pool A. B. C. D. Explanation Comprehensive and Detailed Explanation From BIG-IP Administration S73upport and Troubleshooting documents: Persistence is critical for ensuring that a client's session remains with the same pool member throughout its duration. If primary persistence (like Cookie Persistence) fails—for instance, because the client has disabled cookies—load balancing will not work as expected, and the session may be broken. A "Fallback Persistence Profile" provides a backup method75. The most common and reliable fallback method is "Source Address Affinity"76. This method tracks the client's IP address in the BIG-IP's persistence table and ensures that any subsequent requests from that IP are routed to the same pool member, even if the primary persistence token is missing. Troubleshooting session drops often involves checking if a fallback method is configured to handle scenarios where the primary method is unsupported by the client's browser or environment. Without a fallback, the BIG-IP would revert to standard load balancing, potentially sending the client to a different server that lacks their session data. Question #:5 - [Identify the reason a pool is not working as expected] Which two methods should the BIG-IP Administrator use to troubleshoot a pool member that has been marked by its health monitor? (Choose two answers) DOWN Review the BIG-IP routing table using netstat -rn to show all routes. Enable monitor logging for the pool member that is DOWN Review the pool and pool-member statistics table for error data. Collect a TCPdump packet capture for the pool member. DOWN Answer: B D Explanation When a pool member is marked , it indicates that the configured health monitor is failing. The most DOWN effective troubleshooting approach is to focus on the monitor behavior and the actual traffic between BIG-IP and the pool member. Enabling monitor logging (Option B) is a recommended first step. Monitor logging provides detailed information about why the health check is failing, such as timeouts, connection refusals, incorrect responses, or unexpected status codes. This directly correlates with BIG-IP troubleshooting best practices and allows administrators to confirm whether the failure is due to application behavior, incorrect monitor configuration, or network reachability. Collecting a TCPdump packet capture (Option D) is also a highly effective method. A packet capture allows the administrator to verify whether the monitor probes are being sent, whether responses are received, and whether packets are being dropped, reset, or malformed. This is especially valuable when diagnosing firewall issues, SSL problems, or application-level failures. Reviewing pool statistics (Option C) is useful for general monitoring but does not explain a health monitor why is failing. Reviewing the routing table (Option A) is typically unnecessary unless there is evidence of a broader routing issue affecting multiple destinations. F5 - F5CAB5 Certs Exam 5 of 8 Pass with Valid Exam Questions Pool A. B. C. D. A. B. Question #:6 - [Identify the reason a pool is not working as expected] A BIG-IP Administrator observes the following pool member status message: Pool /Common/testpool member /Common/10.120.0.5:8090 monitor status down [/Common/http: up, /Common/http2: down; last error:] Why is this pool member being marked down? (Choose one answer) The pool member is currently only serving HTTP traffic. The pool member is currently only serving TCP traffic. The pool member is currently only serving UDP traffic. The pool member is currently only serving HTTPS traffic. Answer: A Explanation The pool member is marked because it is monitored by , specifically an DOWN multiple health monitors monitor and an monitor. The status message clearly shows that the , HTTP HTTP/2 HTTP monitor is UP while the . In BIG-IP, when multiple monitors are assigned to a pool member, the HTTP/2 monitor is DOWN default behavior is , meaning for the pool member to be AND logic all assigned monitors must succeed considered healthy. In this scenario, the server is responding successfully to standard HTTP (likely HTTP/1.1) requests but does not support or respond correctly to HTTP/2 requests. As a result, the HTTP/2 monitor fails, which causes the overall monitor status to be , even though HTTP traffic itself is working. DOWN This behavior is expected and documented in BIG-IP monitoring logic. Unless the monitor rule is explicitly changed to , a single failing monitor will mark the pool member down. Therefore, the correct “at least one of” conclusion is that the pool member is , not HTTP/2. only serving HTTP traffic The resolution would be to either remove the HTTP/2 monitor, correct the application to support HTTP/2, or adjust the monitor rule to match the intended health-check logic. Question #:7 - [Identify the reason a virtual server is not working as expected] Refer to the exhibit. A BIG-IP Administrator creates a new Virtual Server to load balance SSH traffic. Users are unable to log on to the servers. What should the BIG-IP Administrator do to resolve the issue? (Exhibit shows a Standard Virtual Server with an HTTP profile applied). Set Protocol to UDP8 Set HTTP Profile to None9 F5 - F5CAB5 Certs Exam 6 of 8 Pass with Valid Exam Questions Pool C. D. A. B. C. D. Set Source Address to 10.1.1.210 Set Destination Addresses/Mask to 0.0.0.0/011 Answer: B Explanation Comprehensive and Detailed Explanation From BIG-IP Administration Supp13ort and Troubleshooting documents: When troubleshooting a Virtual Server that is not working as expected, it is critical to ensure that the applied profiles match the type of traffic being processed. SSH (Secure Shell) is a non-HTTP protocol that operates over TCP. The exhibit indicates that an HTTP profile is applied to the Virtual Server14. An HTTP profile instructs the BIG-IP system to parse traffic as HTTP; however, since SSH traffic does not follow HTTP specifications, the BIG-IP's parser will fail to understand the data stream, typically resulting in dropped packets or reset connections15. To fix this, the administrator must set the HTTP profile to "None"16. This allows the Virtual Server to act as a "Standard" or "FastL4" listener that passes the encrypted SSH data transparently to the backend pool members without attempting application-layer inspection. This highlights a common troubleshooting step: verifying that L7 profiles are not inadvertently applied to L4 traffic, which disrupts the expected traffic flow between the client and the server. Question #:8 - [Identify the reason a virtual server is not working as expected] A BIG-IP Administrator creates a new Virtual Server. The end user is unable to access the page. During troubleshooting, the administrator learns that the connection between the BIG-IP system and server is NOT set up correctly. What should the administrator do to solve this issue? Disable Address Translation Set Address Translation to Auto Map, configure a SNAT pool, and have pool members in the same subnet of the servers Set Address Translation to SNAT and configure a specific translation address Set Address Translation to SNAT and have self-IP configured in the same subnet of servers Answer: C Explanation When a virtual server is not working as expected despite the pool members being marked "UP" (Green), the issue is frequently a return-path routing failure. If the BIG-IP forwards a request with the original client's source IP address, the backend server will try to respond directly to that client. If the server does not have its default gateway pointed back to the BIG-IP, the response packet will be routed elsewhere (or dropped), resulting in a connection timeout for the user. To resolve this, the administrator must configure "Source Address Translation" (SNAT). By setting SNAT to "Automap" or a specific SNAT address, the BIG-IP replaces the client's IP with its own internal self-IP. The backend server then sees the BIG-IP as the source and sends the response back to it locally. This troubleshooting step ensures a functional, symmetric tr18affic flow. Identifying the need for SNAT is one of the most common troubleshooting tasks for new virtual server deployments where the BIG-IP is not the default gateway for the backend servers. F5 - F5CAB5 Certs Exam 7 of 8 Pass with Valid Exam Questions Pool A. B. C. D. E. A. B. C. Question #:9 - [Identify the reason load balancing is not working as expected] A BIG-IP Administrator plans to upgrade a BIG-IP device to the latest TMOS version. Which two tools could the administrator leverage to verify known issues for the target versions? (Choose two answers) F5 End User Diagnostics (EUD) F5 Bug Tracker F5 University F5 iHealth F5 Downloads Answer: B D Explanation Before upgrading a BIG-IP system to a newer TMOS version, it is critical to review known issues to avoid introducing instability or regressions. is a primary resource for this purpose. It F5 Bug Tracker (Option B) allows administrators to search for documented software defects by TMOS version, module, symptom, or bug ID. Using Bug Tracker, an administrator can identify unresolvedissues, fixed bugs, and behavioral changes that may affect their specific deployment, such as traffic handling, high availability, or module-specific functionality. This directly supports proactive troubleshooting and informed upgrade planning. F5 iHealth (Option D) is another essential tool used during upgrade preparation. iHealth analyzes uploaded UCS or QKView files and correlates the device configuration and software version with F5’s known issues database. It provides actionable reports highlighting critical defects, upgrade risks, interoperability concerns, and recommended target versions. iHealth is especially valuable because it contextualizes known issues based on the actual configuration running on the device. The other options are not appropriate for verifying known software issues. F5 End User Diagnostics (Option is a client-side troubleshooting tool, is a training platform, and A) F5 University (Option C) F5 Downloads is primarily used to obtain software images and release notes, not to analyze known defects in (Option E) depth. Question #:10 - [Identify the reason load balancing is not working as expected] A set of servers is used for an FTP application as well as an HTTP website via separate BIG-IP Pools. The server support team reports that some servers are receiving a lot more traffic than others. Which Load Balancing Method should the BIG-IP Administrator apply to even out the connection count? Ratio (Member) Least Connections (Member) F5 - F5CAB5 Certs Exam 8 of 8 Pass with Valid Exam Questions Pool C. D. Least Connections (Node) Ratio (Node) Answer: C Explanation When load balancing is not working as expected across hardware hosting multiple services, the administrator must distinguish between "member" and "node" level algorithms102102102102. A "member" is a specific IP and port (e.g., 10.1.1.1:80), while a "node" is the physical server's IP (10.1.1.1) regardless of the port103. If servers host both FTP and HTTP services in separate pools, using "Least Connections (Member)" only balances connections within each individual pool. This can lead to a skewed distribution where one server is selected for a new HTTP connection because it has the fewest HTTP connections, even if it is currently overloaded with hundreds of FTP connections. By applying "Least Connections (Node)," the BIG-IP tracks the total number of connections to the physical hardware across all ports and pools106106106106. This ensures that the administrator can maintain an even distribution of the total workload across the server fleet, resolving the reports of uneven traffic distribution reported by the server support team About certsout.com certsout.com was founded in 2007. We provide latest & high quality IT / Business Certification Training Exam Questions, Study Guides, Practice Tests. We help you pass any IT / Business Certification Exams with 100% Pass Guaranteed or Full Refund. Especially Cisco, CompTIA, Citrix, EMC, HP, Oracle, VMware, Juniper, Check Point, LPI, Nortel, EXIN and so on. View list of all certification exams: All vendors We prepare state-of-the art practice tests for certification exams. You can reach us at any of the email addresses listed below. 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