F5 101 Exam Dumps & Practice Test Questions
Question No 1:
Which four methods listed below can GTM use to assess the status and performance of BIG-IP and servers? (Select four.)
A. ping
B. Application monitors
C. Inband monitors
D. SSH
E. iQuery
F. SNMP
Answer: B, C, E, F
Explanation:
In Global Traffic Manager (GTM), monitoring the status and performance of BIG-IP and associated servers is crucial for maintaining system health and ensuring optimal traffic routing. GTM uses various monitoring methods to gather performance data and determine the availability of servers. Let’s explore the options listed.
A. ping
While ping is a common network tool used for testing connectivity between devices, it is not specifically the best method for monitoring BIG-IP or server performance in a complex environment like GTM. Ping may be useful for determining if a server is reachable, but it doesn't provide detailed insights into the health or performance of the system. Therefore, this method is not the most effective for GTM monitoring.
B. Application monitors
Application monitors are specialized tools used in GTM to track the health of specific applications hosted on BIG-IP or other servers. They perform a deeper level of checking by testing specific application layers, ensuring that not just the network but also the application is functioning correctly. This is one of the most accurate ways to monitor the overall status of services, making it a key choice for GTM.
C. Inband monitors
Inband monitors refer to monitoring techniques where the health and performance data are gathered from within the network infrastructure. These monitors operate directly within the data path and provide insights into traffic, performance, and network behavior, making them an excellent option for GTM to assess the state of servers in real time.
D. SSH
SSH (Secure Shell) is a method of securely accessing servers to manage and configure them. While SSH allows administrative control, it is not a monitoring tool itself. It is useful for troubleshooting but does not actively monitor server performance or health, so it is not part of GTM’s primary monitoring tools.
E. iQuery
iQuery is a protocol used by GTM to query information about the status and performance of DNS servers. It provides real-time monitoring of server health and performance, allowing GTM to gather detailed data about DNS server availability. This makes iQuery a key component of the GTM monitoring setup.
F. SNMP
Simple Network Management Protocol (SNMP) is widely used for network monitoring. It enables GTM to collect performance and status data from devices like BIG-IP and other network equipment. SNMP is an essential monitoring tool for collecting detailed metrics on server health, bandwidth usage, and error conditions. Therefore, SNMP is a reliable and integral method for GTM to assess system performance.
In summary, GTM uses application monitors, inband monitors, iQuery, and SNMP to effectively track the health and performance of BIG-IP and servers, while ping and SSH are less critical for routine performance monitoring.
Question No 2:
What occurs when the data center recommended by GTM for a client is unavailable?
A. GTM uses cached information to determine an alternate route.
B. GTM queries the local DNS server.
C. GTM sends subsequent queries to the next preferred data center.
D. GTM directs the client to use its DNS cache to select an alternate location.
E. The client continues to attempt to access the preferred data center.
Answer: C
Explanation:
Global Traffic Manager (GTM) is responsible for intelligently managing traffic across multiple data centers to ensure optimal performance and availability for end users. In the event that the recommended data center becomes unavailable, GTM must take action to reroute traffic to an alternative location to maintain the continuity of service for clients.
A. GTM uses cached information to determine an alternate route.
While GTM may leverage cached data to make routing decisions in some cases, it does not depend on this method as the primary solution when a recommended data center is unavailable. Cached information generally serves as a backup but doesn't typically guide GTM's decision to reroute traffic. Therefore, this option is not the most appropriate response when the primary data center is down.
B. GTM queries the local DNS server.
This action would not directly resolve the issue at hand. GTM doesn’t query the local DNS server to find an alternative when a data center is unavailable. It is responsible for managing traffic at a global scale, and its routing decisions are based on the health of the data centers and the configuration of the system. While DNS queries are involved in GTM's operation, it doesn't use local DNS servers for determining alternate routes in real-time when a data center fails.
C. GTM sends subsequent queries to the next preferred data center.
When the recommended data center is unavailable, GTM uses its failover and load-balancing mechanisms to send subsequent queries to the next preferred data center. This ensures that clients are directed to a functioning data center, helping to maintain service availability without interruption. This method is in line with the core functionality of GTM, which is to ensure seamless traffic routing and minimize downtime.
D. GTM directs the client to use its DNS cache to select an alternate location.
While clients may have DNS caches locally, GTM’s responsibility is to manage traffic at a higher level. It does not typically direct clients to use their DNS cache to select an alternative location. Instead, GTM itself handles the rerouting by determining the best available data center. The client’s DNS cache would only be relevant if the client attempts to access the site again after the failure, but this is not the immediate response when a data center is unavailable.
E. The client continues to attempt to access the preferred data center.
If GTM's failover mechanisms were not in place, the client would keep attempting to access the failed data center, leading to potential delays or failures in service. However, GTM actively prevents this scenario by rerouting the client to the next best available data center. Therefore, this option is not correct, as it does not reflect the automatic failover functionality GTM provides.
In summary, when the data center that GTM recommends for a client becomes unavailable, GTM takes action to send subsequent queries to the next preferred data center, ensuring that the client is redirected to a functioning location to maintain service continuity.
Question No 3:
Can GTM distribute traffic to LTM as well as non-BIG-IP hosts?
A. True
B. False
Answer: B
Explanation:
GTM (Global Traffic Manager) is a product from F5 Networks that is responsible for directing and managing traffic across multiple locations or data centers. It works at the DNS (Domain Name System) level to ensure that traffic is routed efficiently, whether it's for load balancing or disaster recovery. GTM is part of the BIG-IP product family but has the ability to direct traffic to various types of systems, not just other BIG-IP devices like LTM (Local Traffic Manager).
The key point to understand here is the relationship between GTM and LTM. GTM is designed primarily to perform global load balancing, which involves directing traffic to the most appropriate data center or server based on factors like performance, availability, and proximity. LTM, on the other hand, deals with local traffic management within a data center, optimizing traffic distribution between servers.
However, GTM does not limit itself to only distributing traffic to other BIG-IP devices like LTM. It has the capability to direct traffic to non-BIG-IP systems as well. This is achieved by configuring GTM with a variety of load balancing methods, such as DNS-based methods or by using specific health checks to ensure that non-BIG-IP systems are available and responsive. For instance, GTM can use DNS records to point to servers outside the BIG-IP ecosystem, ensuring that non-BIG-IP systems are part of the load-balancing setup.
In contrast, if GTM were restricted to load balancing only to LTM devices, its utility in a hybrid environment (where multiple different types of systems are used) would be significantly reduced. Therefore, GTM's ability to distribute traffic not just to LTM but also to non-BIG-IP hosts is an essential feature for flexible, scalable, and robust traffic management across various infrastructures.
In conclusion, GTM can indeed load balance to both LTM devices and non-BIG-IP hosts, making it versatile for diverse network environments.
Question No 4:
Which of the following is NOT found on the F5 DevCentral website?
A. Subscription purchasing options
B. Actual iRules written by other customers
C. iRules reference materials
D. Forums
E. The F5 iRule editor
Answer: A
Explanation:
The F5 DevCentral site is a community-driven platform designed to support developers, network engineers, and IT professionals who work with F5 products, especially the F5 BIG-IP platform. It provides a range of resources and tools, but it does not focus on direct purchasing options for subscriptions. Therefore, A. Subscription purchasing options is the correct answer as it is not typically a focus of DevCentral.
The website primarily focuses on providing a wide array of technical resources and tools that can help users get the most out of F5 products, such as B. Actual iRules written by other customers. iRules are custom scripts used within the F5 BIG-IP to control traffic flow, and the site allows users to share these scripts with each other, facilitating collaboration and knowledge sharing.
In addition to user-contributed iRules, C. iRules reference materials are available to help users better understand how to write and implement iRules. These reference materials often include tutorials, best practices, and code snippets that can be very useful for troubleshooting and optimizing BIG-IP configurations.
The D. Forums section of DevCentral allows users to interact with the community, ask questions, and share knowledge. These forums are a vital part of the site as they enable members to receive advice from experienced professionals and F5 experts.
Additionally, the F5 iRule editor is a tool provided by F5 to help users create, test, and manage iRules. This editor is accessible through DevCentral and is designed to streamline the process of writing and debugging iRules. Therefore, E. The F5 iRule editor is indeed part of the site.
In conclusion, while F5 DevCentral offers a variety of technical resources, A. Subscription purchasing options is not part of the platform's focus, which is why it is the correct answer.
Question No 5:
If LTM is using the "least connections" load balancing method, which pool member will get the next request according to the provided diagram?
A. A
B. B
C. C
D. D
Answer: D
Explanation:
The "least connections" method in LTM (Local Traffic Manager) is a load balancing technique that directs traffic to the server or pool member with the least number of active connections. This approach ensures that servers or pool members that are less busy receive more requests, which helps to distribute traffic more evenly and prevents any single server from becoming overwhelmed.
In a scenario where LTM is configured to use the least connections method, each pool member will maintain a count of active connections at any given time. When a new request arrives, LTM evaluates the number of active connections for each pool member and selects the one with the fewest connections to handle the request. This method helps to maintain balanced server loads, improving overall performance and reliability.
For instance, if pool member A has 10 active connections, pool member B has 5, pool member C has 7, and pool member D has 3, LTM will direct the new request to pool member D, as it has the fewest active connections. By routing traffic to the least busy pool member, LTM ensures that no individual server becomes overloaded, leading to better performance and faster response times.
It’s important to note that this method does not necessarily mean that the pool member with the least overall capacity (in terms of hardware or resources) is chosen. Rather, it’s purely based on the number of active connections at the moment the request is received. The goal is to achieve a balanced load across the pool members, ensuring that all servers contribute to handling requests in an efficient manner.
This approach is particularly useful in scenarios where the workload is unpredictable or where different servers may have different processing power or capabilities. By using the least connections method, LTM can adaptively balance the load in real time.
Question No 6:
What happens when the LTM (Local Traffic Manager) pool member is marked as disabled"?
A. LTM will continue to route traffic to the disabled pool member, but it will not accept new connections.
B. LTM will not route traffic to the disabled pool member, and any connections will be redirected to other members.
C. LTM will send all incoming traffic to the disabled pool member, assuming it will become active again soon.
D. LTM will delete the pool member from the pool and stop monitoring it.
Answer: B
Explanation:
In F5 LTM (Local Traffic Manager), pool members are servers or resources that handle client requests. These pool members are actively monitored, and their availability is essential for efficient traffic management. When a pool member is marked as "disabled," LTM is instructed not to route traffic to that member, and any new incoming requests will be redirected to other available pool members.
How LTM handles disabled pool members:
When a pool member is disabled, it no longer participates in traffic handling for new incoming requests. Although the pool member remains part of the configuration, it is essentially removed from the active pool of servers receiving traffic. Importantly, existing connections that were previously directed to the disabled pool member are not abruptly terminated. LTM allows these connections to finish processing, ensuring that no ongoing sessions are disrupted.
The primary reason for disabling a pool member is often for maintenance or troubleshooting purposes. For example, an administrator may disable a pool member while conducting server updates or repairs. During this time, LTM automatically redirects traffic to other healthy pool members, maintaining uninterrupted service for end users.
Why the other options are incorrect:
A. LTM will continue to route traffic to the disabled pool member, but it will not accept new connections.
This is incorrect. When a pool member is disabled, LTM stops routing all traffic to that member. No new traffic is directed to the disabled member, and the system reassigns requests to other healthy pool members.
C. LTM will send all incoming traffic to the disabled pool member, assuming it will become active again soon.
This is not accurate. If a pool member is disabled, LTM actively avoids routing traffic to that member, regardless of whether it is expected to become active soon. This is done to prevent issues if the server is unavailable or undergoing maintenance.
D. LTM will delete the pool member from the pool and stop monitoring it.
This is incorrect. Disabling a pool member does not remove it from the pool or stop monitoring it. The pool member is still part of the configuration and is continually monitored by LTM. Once the issue is resolved, the member can be re-enabled and traffic will be routed to it again.
When a pool member is marked as "disabled" in F5 LTM, LTM stops routing new requests to that member but allows existing sessions to complete. This feature ensures that administrators can perform maintenance without causing disruptions in service for clients. Therefore, option B is correct, as it accurately describes the behavior of LTM when a pool member is disabled.
Question No 7:
How does LTM determine the best pool member to handle an incoming request when using the "Round Robin" load balancing method?
A. LTM sends the request to the pool member with the least number of active connections.
B. LTM sends the request to the pool member with the highest processing power.
C. LTM sends the request to the pool members in a fixed, sequential order.
D. LTM sends the request to the pool member with the most recent health check success.
Answer: C
Explanation:
When using the Round Robin load balancing method, LTM distributes incoming requests to pool members in a sequential and circular manner. It sends the first request to the first pool member, the second request to the next pool member, and so on. After reaching the last pool member, it loops back to the first member. This approach ensures that each pool member receives an equal share of traffic, providing a simple yet effective means of load balancing. It does not take into account the server’s load, health, or performance, which are factors managed by other load balancing methods such as least connections.
A. LTM sends the request to the pool member with the least number of active connections.
This describes the least connections load balancing method, not Round Robin. The Round Robin method does not consider active connections; it just distributes requests evenly.
B. LTM sends the request to the pool member with the highest processing power.
The Round Robin method does not prioritize servers based on processing power or performance metrics. It is based solely on a sequential order.
D. LTM sends the request to the pool member with the most recent health check success.
This is more in line with a weighted or priority-based load balancing method, where traffic might be routed to the most available or healthy server. However, Round Robin does not take health check success into account when determining traffic distribution.
Question No 8:
What is the purpose of a health monitor in F5 LTM?
A. To track the traffic volume handled by each pool member.
B. To determine whether a pool member is available to handle traffic.
C. To control the amount of traffic each pool member can handle.
D. To encrypt the data being sent to a pool member.
Answer: B
Explanation:
A health monitor in F5 LTM is used to regularly check the availability and health of pool members. The monitor ensures that LTM only directs traffic to servers that are functioning correctly. Health monitors can perform various checks, such as verifying that a server responds to HTTP requests or ensuring that an application running on the server is working properly. If a pool member fails a health check, LTM will temporarily remove it from the pool of available servers and stop sending new requests to it.
A. To track the traffic volume handled by each pool member.
Health monitors are not responsible for tracking traffic volume; their role is to assess the health of servers. Tracking traffic volume is typically done through monitoring tools and reporting systems.
C. To control the amount of traffic each pool member can handle.
Health monitors do not control the amount of traffic sent to each server; that is the function of load balancing methods. Monitors are concerned with the operational status of the servers.
D. To encrypt the data being sent to a pool member.
Encryption is not the responsibility of health monitors. This function is handled by SSL/TLS configurations, which secure data during transmission.
Question No 9:
What happens if an F5 LTM pool member fails a health check?
A. LTM continues to send traffic to the pool member but records the failure.
B. LTM removes the pool member from the pool temporarily and redirects traffic to other members.
C. LTM disables the pool member permanently and stops monitoring it.
D. LTM sends an alert to the administrator but does not take any further action.
Answer: B
Explanation:
When an F5 LTM pool member fails a health check, it is temporarily removed from the list of available servers, and LTM redirects traffic to the other healthy members of the pool. The pool member is not permanently disabled but is excluded from receiving traffic until it passes a health check again. This ensures that traffic is only routed to servers that are fully functional and capable of handling requests, maintaining high availability and reliability for users.
A. LTM continues to send traffic to the pool member but records the failure.
If a pool member fails a health check, LTM stops routing traffic to it. It does not continue to send traffic to a failed server. This would compromise service availability.
C. LTM disables the pool member permanently and stops monitoring it.
LTM does not permanently disable a pool member after a health check failure. The server is simply removed from the pool until it is healthy again.
D. LTM sends an alert to the administrator but does not take any further action.
LTM actively removes the failed pool member from the pool and reroutes traffic. It does not wait for administrator intervention to take action.
Question No 10:
What is the function of the F5 LTM "iRules" feature?
A. To assign traffic routing decisions based on SSL certificates.
B. To monitor and log the health of pool members.
C. To customize and control how LTM handles network traffic.
D. To encrypt traffic between LTM and pool members.
Answer: C
Explanation:
iRules in F5 LTM are a powerful scripting tool that allows administrators to define and control how LTM processes and handles network traffic. iRules are written in a language called TCL (Tool Command Language) and provide fine-grained control over aspects like traffic routing, load balancing, content rewriting, and more. They enable LTM to perform complex traffic management tasks, such as redirecting HTTP traffic, modifying headers, or blocking certain types of requests based on custom conditions.
A. To assign traffic routing decisions based on SSL certificates.
While SSL/TLS offloading and certificate handling are important tasks for LTM, iRules do not specifically handle routing based on SSL certificates. iRules can be used to inspect or modify SSL traffic, but their primary function is not to assign routing decisions based on certificates.
B. To monitor and log the health of pool members.
Health monitoring is handled through health monitors, not iRules. iRules can interact with traffic, but they are not used specifically for health checks.
D. To encrypt traffic between LTM and pool members.
Encryption of traffic between LTM and pool members is typically managed through SSL profiles and not iRules. iRules do not directly control encryption; instead, they modify traffic at a higher level.
