Pass the F5-CA F5CAB3 Questions and answers with Dumpstech

Using “at least one” ensures each member is marked up based on its relevant service monitor.

Fallback persistence is used when the primary persistence method fails. Source Address Affinity is a Layer 4 persistence method and is fully supported as a fallback option for most virtual server types.

In this scenario, each backendnode (server)hosts multiple services and is referenced by multiple pools and virtual servers. The goal is to ensure anequal number of total connections per backend server, regardless of how many pool members (services/ports) exist on that server.

According to theBIG-IP Administration: Data Plane Configurationdocumentation:

Least Connections (node)tracks the total number of active connections to anode across all pool members and services.

This algorithm ensures load distribution is balanced at theserver level, not just at the individual service (member) level.

It is specifically recommended when:

Multiple pool members exist on the same backend server

Multiple virtual servers reference the same backend servers

Why the other options are incorrect:

B. Predictive (member)Predictive algorithms are advanced and traffic-pattern based, but they operate at the member level and do not guarantee equal connections per server.

C. Least Connections (member)This balances connections per pool member, which can overload a server hosting multiple members while still appearing “balanced” per member.

D. Predictive (node)Although node-aware, predictive algorithms are less deterministic and not the best choice when strict equality of connections is required.

Correct Resolution:

UsingLeast Connections (node)ensures that each backend server carries an equal connection load across all services and pools.

X-Forwarded-For inserts the original client IP into HTTP headers while SNAT is enabled.

Forwarding (IP) virtual servers forward traffic based on routing decisions and do not use pools or pool members.

A red diamond indicates the Virtual Server is enabled but unavailable due to all pool members being down.

Slow Ramp Time prevents new pool members from receiving full traffic immediately, avoiding overload.

A red diamond indicates that the Virtual Server is enabled but unavailable, typically due to all pool members being down.

WAN-optimized TCP profiles improve performance for high-latency Internet clients, while LAN profiles are optimal for backend servers.

In BIG-IP systems,iRules influence traffic only when they are attached to a Virtual Server. If application traffic is being sent tonodes or pool members that are not defined in the pool, this typically indicates that an iRule is overriding the default load-balancing behavior by explicitly selecting a pool or node.

According toBIG-IP Administration: Data Plane Configurationand official F5 guidance:

iRules areassociated with Virtual Servers, not directly with pools or nodes.

To determine whether an iRule is actively affecting traffic, the administrator must inspect theVirtual Server configuration.

Explanation of the correct answers:

B. Via the GUI at the Resources tab for the virtual serverTheResourcestab in the Configuration Utility displays all traffic-handling objects applied to the Virtual Server, includingassigned iRules. This is the primary GUI location to verify whether an iRule is influencing data plane traffic.

C. Via TMSH with the list /ltm virtual <virtual_server> commandThis TMSH command displays the full Virtual Server configuration, including anyiRules listed under the rules section. It is the authoritative CLI method to confirm iRule usage.

Why the other options are incorrect:

A. Via TMSH with the list /ltm rule <irule> commandThis command only shows the contents of an iRule and does not indicate whether the iRule is attached to or used by any Virtual Server.

D. Via the GUI at the iRule tab for the virtual serverBIG-IP does not provide a dedicated “iRule” tab on Virtual Servers. iRules are viewed and managed under theResourcestab.

Correct Conclusion:

To verify whether an iRule is responsible for unexpected node selection, the BIG-IP Administrator must examine theVirtual Server configuration, either through theResources tab in the GUIor by usingTMSH to list the Virtual Server configuration.