F5CANR F5 Certified Administrator, NGINX Recertification Exam Practice Questions
Prepare for F5CANR with more than an answer.
- Exam fee
- $100 USD
- Time limit
- 60 minutes
- Questions on the exam
- 50
- Passing score
- 245
- Level
- Administrator (Recertification)
- Valid for
- Renews the F5-CA, NGINX credential per F5's certification lifecycle
Domains covered on the exam 4
- NGINX Management25%
- NGINX Configuration: Knowledge25%
- NGINX Configuration: Demonstrate31%
- NGINX Troubleshooting19%
- 1
To limit the number of concurrent connections per client IP address, an administrator must first define a shared memory zone. Which of the following is the correct syntax to define a 10-megabyte connection limiting zone named 'limitperip' based on the client's binary IP address?
Show answer details
Correct answer: A
This is the correct syntax. The 'limit_conn_zone' directive requires the key (in this case, '$binary_remote_addr' which is more memory-efficient than '$remote_addr') followed by the 'zone=' parameter defining the name ('limitperip') and the size ('10m').
- 2
When configuring NGINX as a content cache, you use the
proxy_cache_pathdirective, which requires defining akeys_zone. What exactly is stored within the shared memory allocated by thiskeys_zoneparameter?Show answer details
Correct answer: B
The 'keys_zone' allocates shared memory specifically for cache metadata (keys, pointers to the files on disk, size, and expiration). The actual cached content payloads are stored on the file system at the path specified in the directive, not in the shared memory zone itself.
flowchart LR A[keys_zone Shared Memory] -->|Contains| B[Cache Keys & Timers] A -->|Points to| C[proxy_cache_path Disk Storage] C -->|Contains| D[Actual Response Payloads] - 3
An organization has a cluster of three backend application servers. Server A has 32 cores, while Servers B and C have 8 cores each. The administrator wants NGINX to distribute traffic such that Server A receives proportionally more requests than the others, while still utilizing all three servers. Which configuration block achieves this?
Show answer details
Correct answer: B
In an NGINX upstream block, the 'weight' parameter is used to direct more traffic to specific servers. By default, the weight is 1. Setting Server A's weight to 4 means it will receive roughly 4 times as many requests as Server B or C, which aligns with its higher core count. 'priority' is not a valid parameter for this purpose.
- 4
An administrator is configuring passive health checks in NGINX Open Source for an upstream group of web servers. They want NGINX to mark a backend server as unavailable if it fails to respond 3 times within a 15-second window, and keep it marked as unavailable for 30 seconds before trying it again. Which TWO parameters must be added to the
serverdirective in the upstream block? (Select TWO)Show answer details
Correct answer: A, B
The 'max_fails' parameter sets the number of unsuccessful attempts to communicate with the server that should happen in the duration set by the 'fail_timeout' parameter to consider the server unavailable. Here, max_fails=3 is required.
The 'fail_timeout' parameter serves two purposes: it defines the time frame during which the specified number of unsuccessful attempts (max_fails) must occur, and it also defines how long the server will be considered unavailable after it has failed. Setting this to 30s fulfills the requirement.
- 5
A systems architect is designing a highly available web architecture. They need a component that can terminate TLS connections, serve static assets directly from disk to reduce backend load, and distribute dynamic API requests across a pool of application servers based on their current connection count. Which NGINX role best encompasses all these requirements?
Show answer details
Correct answer: C
NGINX operating as a Reverse Proxy and Load Balancer perfectly fits this scenario. It can terminate TLS, serve static files using the 'root' directive before forwarding requests, and use upstream blocks with 'least_conn' to distribute dynamic traffic. While it acts as a web server for the static files, the overarching role managing the API distribution and TLS termination for backends is a reverse proxy/load balancer. A standalone web server would not distribute traffic, and a CDN Edge is a broader infrastructure concept rather than the specific NGINX role described.
- 6
A large enterprise is redesigning its ingress architecture for a Kubernetes-based microservices environment. The current setup experiences high latency due to TLS handshakes being renegotiated at multiple hops, and static media files are unnecessarily traversing the internal network to reach backend pods.
The new requirements dictate:
- TLS must be terminated at the edge.
- Static media (/images/, /video/) must be served from memory or disk at the edge.
- API requests must be routed to the correct internal microservice based on the URI path.
- Microservice responses must be cached for 5 minutes unless the client sends a 'Cache-Control: no-cache' header.
Based on these requirements, how should NGINX be positioned and configured in this architecture?
flowchart TD Client([Client]) --> NGINX[NGINX Edge] NGINX -->|/images/| Disk[(Local SSD)] NGINX -->|/api/v1/| PodA[Auth Service] NGINX -->|/api/v2/| PodB[Data Service]Show answer details
Correct answer: B
This approach correctly addresses all requirements. NGINX operates at Layer 7 to inspect URIs (routing /api/v1 vs /api/v2), terminates TLS using 'ssl_certificate', serves static files directly via the 'root' directive in a specific location, and utilizes 'proxy_cache_bypass $http_cache_control' to respect client cache-busting requests. Layer 4 load balancing (stream module) cannot inspect URIs or serve static files. Terminating TLS at the pods violates the edge-termination requirement.
