F5-CTS-LTM Practice Test 2 — 10 Questions

Question 1

Refer to the exhibit. A user connects to Virtual Server A, which uses the 'my_source_persistence' profile. The user is then redirected to Virtual Server B. Given the configuration, will the persistence record be honored?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

No, because match-across-virtuals is disabled.. The persistence profile has 'match-across-virtuals' set to 'disabled'. Because this attribute is disabled, the BIG-IP will not share persistence information between Virtual Server A and Virtual Server B. When the user lands on Virtual Server B, the system will initiate a new load balancing decision instead of respecting the persistence session established on the first virtual server, which is crucial for managing multi-virtual server architectures.

Answer

Yes, because the timeout is set to 180 seconds.

Answer

Yes, because source-addr persistence is global.

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No, because the timeout must be set to indefinite.

Question 2

Which TWO of the following are primary benefits of using an iApp Template for BIG-IP deployment?

Accepted Answer

Simplified management by grouping related LTM objects into a single logical entity.. iApp templates provide a structured, simplified interface for deploying complex applications. By abstracting the creation of multiple objects (virtual servers, pools, profiles, iRules) into a single deployment unit, they reduce the risk of human error and configuration drift. These templates are essential for maintaining consistency across large environments and ensuring that best practices are followed during every configuration step.

Answer

Automatic translation of proprietary application logic into F5 proprietary TCL scripts.

Answer

Direct execution of remote SQL queries to backend database servers for load balancing.

Answer

Automatic hardware upgrades of the BIG-IP platform when capacity is reached.

Question 3

You have a requirement to distribute traffic to pool members based on the total number of active connections each server is currently handling. Which load balancing method should be selected?

Accepted Answer

Least Connections (member). The 'Least Connections' method is the correct choice for load balancing based on active session counts. This algorithm dynamically tracks the current load on each server and directs new requests to the member with the fewest active connections. It is essential for application environments where individual requests vary significantly in duration or resource consumption, preventing any single server from becoming overwhelmed.

Answer

Round Robin

Answer

Ratio (member)

Answer

Observed (member)

Question 4

Refer to the exhibit. The web_pool is currently offline with zero active members. An LTM Specialist checks the backend servers and finds they are both responding to pings. What is the most likely reason for the pool being offline?

Accepted Answer

The health monitor is misconfigured or the service is down.. The pool status is 'offline' and 'children are down' despite servers being reachable via ping. This indicates the health monitor configured on the pool is failing, likely because the specific service (e.g., HTTP on port 80) is not responding or the monitor is misconfigured. Ping only tests network layer connectivity, whereas LTM monitors test application-layer availability, which is the standard for determining if a server can actually process traffic.

Answer

The virtual server is disabled.

Answer

The default route on the BIG-IP is missing.

Answer

The SNAT pool is exhausted.

Question 5

Why would an LTM Specialist choose to implement a SNAT Automap instead of a SNAT pool?

Accepted Answer

To reduce administrative overhead for simple configurations.. SNAT Automap is the simplest way to manage source translation because it automatically uses the BIG-IP's floating self-IP address. It is ideal for environments where a dedicated pool of IP addresses is not required. This reduces administrative complexity and configuration overhead, which is beneficial for smaller deployments or scenarios where the backend servers only need to see the BIG-IP as the source of traffic.

Answer

To increase security by using multiple source IP addresses.

Answer

To prevent port exhaustion on the BIG-IP.

Answer

To allow backend servers to track unique client IP addresses.

Question 6

An administrator implements Priority Group Activation on a pool containing four web servers. Two servers are assigned priority 10, and two servers are assigned priority 5. The minimum active members parameter is set to 2. One priority 10 member fails. What is the precise traffic distribution behavior of the BIG-IP system?

Accepted Answer

Traffic is balanced exclusively between the single remaining priority 10 member and the two priority 5 members.. Priority Group Activation directs traffic to the highest available priority group until the number of active members in that group drops below the specified minimum active members threshold. When one priority 10 member fails, one remains active, which is below the minimum threshold of 2, triggering activation of the lower priority group while keeping the remaining priority 10 member active.

Answer

Traffic ceases entirely for all pool members until administrators manually intervene and adjust the priority group thresholds via TMOS.

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Traffic distribution shifts completely to the two priority 5 servers, and the remaining priority 10 server is taken offline immediately.

Answer

Traffic is distributed strictly among the two priority 5 servers while the remaining priority 10 server acts as a standby hot spare.

Question 7

An administrator observes that the BIG-IP is not correctly load balancing traffic across all members of a pool. What is the most likely cause if the load balancing method is set to 'Least Connections'?

Accepted Answer

Persistence is enabled, causing the BIG-IP to bypass the load balancing algorithm for existing sessions.. The 'Least Connections' method is highly dependent on the accuracy of the connection table. If persistence is configured, the BIG-IP will ignore the least connections algorithm for any request that is part of an existing session. This is a frequent point of confusion where administrators expect even distribution but see skewed results because users are 'stuck' to specific servers due to their persistence records.

Answer

The pool members are in different subnets, preventing the load balancer from seeing all connections.

Answer

The 'Ratio' load balancing method is implicitly overriding the 'Least Connections' setting.

Answer

The TCP profile is set to 'OneConnect', which prevents the tracking of individual connections.

Question 8

Refer to the exhibit. Why would an administrator enable 'map-to-ipv6' in a source-address persistence profile?

Accepted Answer

It creates a unified persistence table for both IPv4 and IPv6 clients.. In dual-stack environments, both IPv4 and IPv6 clients might access the same application. The 'map-to-ipv6' feature ensures that IPv4 addresses are normalized into an IPv6-compatible format within the persistence table. This creates a unified persistence context, allowing the BIG-IP to correctly track and persist traffic from both address types to the same backend server, maintaining session consistency across different network protocols.

Answer

It forces all traffic to be converted to IPv6 for backend server processing.

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It allows the LTM to translate IPv6 client requests to IPv4 backend servers.

Answer

It is required for performance optimization on the BIG-IP management plane.

Question 9

An administrator needs to modify the HTTP response header to hide the server version for security reasons. Which tool is most appropriate?

Accepted Answer

An iRule in the 'HTTP_RESPONSE' event with 'HTTP::header remove Server'.. An iRule using the 'HTTP_RESPONSE' event is the most flexible way to modify headers. Using the 'HTTP::header remove' command, an administrator can strip sensitive version information from the 'Server' header before the response reaches the client. This is a common security hardening task that prevents potential attackers from fingerprinting the backend server version and identifying known vulnerabilities associated with that specific platform.

Answer

A Local Traffic Policy with a 'header' modify action.

Answer

A customized HTTP profile that blocks the 'Server' header.

Answer

A custom monitor with 'header-strip' enabled.

Question 10

Refer to the exhibit. What is the impact of using the 'tcp-lan-optimized' profile on this virtual server?

Accepted Answer

It is inappropriate if the clients are connecting over the Internet.. The 'tcp-lan-optimized' profile is designed for high-speed, low-latency environments like LANs. It modifies TCP settings to be less aggressive than 'tcp-wan-optimized'. Using it on a connection where the client is accessing over the internet (WAN) can result in poor performance, as the settings do not account for the high latency and packet loss typically encountered on public networks compared to local infrastructure.

Answer

It improves performance for clients connecting over long-distance WAN links.

Answer

It provides faster window scaling for high-latency connections.

Answer

It disables TCP keep-alives to save memory on the BIG-IP.