Report Use of iRules F5CAB3 Practice Questions (Page 1)

Questions 1–5

1. 1foundation · easy

   Which of the following is a required component of an iRule?

   • AA pool statement that specifies the backend server group.
   • BA TCL variable declaration at the top of the script.
   • CA log command to record all traffic processed by the iRule.
   • DAt least one event declaration that defines when the iRule logic executes.
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2. 2foundation · easy

   What is a common technique for debugging an iRule that is not behaving as expected?

   • AChanging the virtual server's IP address to a different subnet.
   • BAdding log statements at key points in the iRule to trace execution.
   • CDeleting the iRule and recreating it with the same code.
   • DRestarting the BIG-IP system to reset the iRule engine.
   Reveal Solution Discussion Select an answer first
4. 3application · easy

   A BIG-IP administrator has created an iRule and applied it to a virtual server. The iRule is not producing the expected behavior. Which step should the administrator take FIRST to troubleshoot the issue?

   • AReboot the BIG-IP to clear any cached iRule state.
   • BCheck the pool member's health status to see if the iRule is affecting it.
   • CVerify the iRule is attached to the correct virtual server and that the virtual server is enabled.
   • DDelete the iRule and recreate it from scratch.
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5. 4foundation · easy

   How can an iRule affect the data plane traffic flow?

   • ABy changing the physical network interface configuration of the BIG-IP.
   • BBy updating the BIG-IP's firmware to improve performance.
   • CBy modifying the BIG-IP's routing table to change how packets are forwarded.
   • DBy inspecting and potentially altering the content of requests and responses as they pass through the virtual server.
   Reveal Solution Discussion Select an answer first
6. 5application · medium

   A BIG-IP administrator notices that a virtual server's throughput has decreased significantly after applying a new iRule. The iRule performs a complex regex match on every HTTP request body. What is the most likely reason for the performance impact?

   • AThe iRule is blocking all traffic, and the throughput decrease is due to connection resets.
   • BThe iRule is processing traffic in the data plane, and the regex match adds CPU overhead on every request.
   • CThe iRule is writing logs for every request, and the log I/O is slowing down the data plane.
   • DThe iRule is causing the BIG-IP to send all traffic to a single pool member, creating a bottleneck.
   Reveal Solution Discussion Select an answer first