Conditional logging in Nginx - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is conditional logging in nginx?

Conditional logging in nginx means logging requests only when certain conditions are met, like logging errors but not successful requests.

beginner

Which nginx directive is used to control conditional logging?

The access_log directive with a condition parameter controls conditional logging.

intermediate

How do you disable logging for requests with status code 200 in nginx?

Use access_log /path/to/log combined if=$loggable; where $loggable is 0 for status 200, for example: map $status $loggable { 200 0; default 1; } and then access_log /path/to/log combined if=$loggable;

intermediate

What is the purpose of the map directive in conditional logging?

The map directive creates a variable based on conditions, which can be used to decide if logging should happen.

intermediate

Can you log only error responses (status 400 and above) in nginx?

Yes, by using a map to set a variable to 1 for status codes 400 and above, then using access_log with if to log only when that variable is 1.

Which directive controls logging in nginx?

A access_log

B error_log

C log_format

D server_log

The access_log directive controls logging of client requests.

How do you disable logging for certain requests in nginx?

A Remove the log file

B Use <code>access_log off;</code> globally

C Use <code>error_log off;</code>

D Use <code>access_log /path/to/log combined if=$condition;</code>

You can disable logging conditionally using access_log /path/to/log combined if=$condition;.

What does the map directive do in conditional logging?

A Sets log format

B Defines log file location

C Creates a variable based on conditions

D Starts the nginx server

map creates variables that help decide logging conditions.

To log only error responses (status 400+), what condition should be set?

A $status < 400

B $status >= 400

C $status = 200

D $status = 500

You set a condition to log when status is 400 or higher.

Which of these is a valid way to conditionally log in nginx?

A access_log /var/log/nginx/access.log if=$loggable;

B error_log /var/log/nginx/error.log if=$loggable;

C log_format conditional;

D server_log conditional;

access_log supports conditional logging with the if parameter.

Explain how to set up conditional logging in nginx to log only requests with status codes 400 and above.

Think about how to create a variable that marks error responses and use it in access_log.

Describe the role of the access_log directive and how it can be customized for conditional logging.

Focus on how access_log controls logging and how conditions affect it.