LCA Web Server & Database Administration 4

Question 1

Which Apache module provides SSL/TLS support for HTTPS connections?

Accepted Answer

mod_ssl

Answer

mod_ssl is the Apache module that implements SSL/TLS using the OpenSSL library to enable HTTPS connections.

Question 2

What does the MySQL EXPLAIN statement reveal?

Accepted Answer

The query execution plan chosen by the optimizer

Answer

EXPLAIN shows how MySQL's query optimizer plans to execute a SELECT statement, including index usage and row estimates.

Question 3

In PostgreSQL, what does VACUUM do?

Accepted Answer

Reclaims storage occupied by dead tuples and updates visibility maps

Answer

VACUUM reclaims space from rows deleted or updated (dead tuples) and updates the visibility map to help autovacuum and query planning.

Question 4

Which Nginx directive sets the maximum allowed size of the client request body?

Accepted Answer

client_max_body_size

Answer

client_max_body_size limits the size of the request body; exceeding it returns a 413 Request Entity Too Large error.

Question 5

What is the purpose of Apache's mod_proxy_fcgi module?

Accepted Answer

Forwards requests to FastCGI backends such as PHP-FPM

Answer

mod_proxy_fcgi allows Apache to forward requests to FastCGI applications (like PHP-FPM) using the FastCGI protocol.

(LCA) Certified Linux Administrator Practice Test