F5N3 sample questions

Question 1

A systems engineer is configuring NGINX to protect a backend API from being overwhelmed by sudden traffic spikes. The requirement is to limit requests to 10 per second per IP address, but allow bursts of up to 20 requests to be processed immediately without adding artificial delay. Which configuration block achieves this?

Accepted Answer

limit_req_zone $binary_remote_addr zone=api_limit:10m rate=10r/s;

server {
location /api/ {
limit_req zone=api_limit burst=20 nodelay;
}
}

Answer

limit_req_zone $binary_remote_addr zone=api_limit:10m rate=10r/s;

server {
location /api/ {
limit_req zone=api_limit burst=20;
}
}

Answer

limit_conn_zone $binary_remote_addr zone=api_limit:10m;

server {
location /api/ {
limit_conn api_limit 10;
limit_rate 20;
}
}

Answer

limit_req_zone $binary_remote_addr zone=api_limit:10m rate=20r/s;

server {
location /api/ {
limit_req zone=api_limit burst=10 nodelay;
}
}

Question 2

A video streaming platform wants to allow users to download the first 50 Megabytes of a video file at full speed, but then restrict the download speed to 500 Kilobytes per second for the remainder of the file to save bandwidth. Which combination of NGINX directives should be used?

Accepted Answer

limit_rate 500k;
limit_rate_after 50m;

Answer

limit_conn_rate 500k;
limit_conn_burst 50m;

Answer

proxy_limit_rate 500k;
proxy_buffer_size 50m;

Answer

bandwidth_limit 500k;
bandwidth_delay 50m;

Question 3

To optimize performance, an administrator wants to enable persistent connections (keep-alives) between NGINX and a pool of upstream HTTP/1.1 application servers. Which THREE configurations are required to achieve this? (Select THREE)

Accepted Answer

Define the 'keepalive' directive within the 'upstream' block.

Accepted Answer

Set 'proxy_http_version 1.1;' in the proxy location block.

Accepted Answer

Clear the Connection header by setting 'proxy_set_header Connection "";'.

Answer

Set 'keepalive_timeout 0;' in the 'http' block.

Answer

Enable 'proxy_keepalive on;' in the 'server' block.

Question 4

Company Alpha is running a file hosting service. They are experiencing issues where malicious users open hundreds of slow connections to tie up server resources, but each connection only downloads data at a very slow rate. The architect wants to limit the number of concurrent connections per IP address to 5.

Which directive correctly establishes the shared memory zone required for this connection limiting?

Accepted Answer

limit_conn_zone $binary_remote_addr zone=addr:10m;

Answer

limit_req_zone $binary_remote_addr zone=addr:10m rate=5r/s;

Answer

limit_conn $binary_remote_addr 5;

Answer

zone_limit_conn addr 10m key=$binary_remote_addr;

Question 5

True or False: The NGINX `keepalive_timeout` directive sets the maximum time a keep-alive client connection will stay open on the server side, and its default value is 0 (which disables keep-alives).

Accepted Answer

False

Answer

True

Question 6

An administrator needs to enforce a dynamic bandwidth limit. Clients authenticating as 'premium' users should have no bandwidth limit (0), while 'standard' users should be limited to 100k per second. The user type is extracted to a variable named `$user_bandwidth_limit`.

Which directive correctly applies this dynamic limit in a location block?

Accepted Answer

limit_rate $user_bandwidth_limit;

Answer

set_limit_rate $user_bandwidth_limit;

Answer

bandwidth_throttle $user_bandwidth_limit;

Answer

limit_req rate=$user_bandwidth_limit;

Free F5N3 sample questions

A video streaming platform wants to allow users to download the first 50 Megabytes of a video file at full speed, but then restrict the download speed to 500 Kilobytes per second for the remainder of the file to save bandwidth. Which combination of NGINX directives should be used?

To optimize performance, an administrator wants to enable persistent connections (keep-alives) between NGINX and a pool of upstream HTTP/1.1 application servers. Which THREE configurations are required to achieve this? (Select THREE)

True or False: The NGINX `keepalive_timeout` directive sets the maximum time a keep-alive client connection will stay open on the server side, and its default value is 0 (which disables keep-alives).

6 more free samples are waiting