Keepalive connections in Nginx - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a keepalive connection in nginx?

A keepalive connection allows nginx to reuse the same TCP connection for multiple requests between the client and server, reducing the overhead of opening new connections.

beginner

Which nginx directive enables keepalive connections for upstream servers?

The directive keepalive inside the upstream block enables keepalive connections to upstream servers.

intermediate

What does the keepalive_timeout directive control in nginx?

It controls how long nginx keeps an idle keepalive connection open before closing it.

intermediate

How does enabling keepalive connections improve performance?

It reduces the time and CPU needed to establish new TCP connections by reusing existing ones, leading to faster response times and less resource use.

beginner

What is the default behavior of nginx regarding keepalive connections if not configured?

By default, nginx closes the connection after each request unless keepalive is explicitly enabled.

Which directive in nginx enables keepalive connections to upstream servers?

A keepalive

B proxy_pass

C listen

D server_name

The keepalive directive inside the upstream block enables keepalive connections.

What is the main benefit of using keepalive connections in nginx?

A Increasing the number of open connections

B Encrypting data automatically

C Blocking slow clients

D Reusing TCP connections to reduce overhead

Keepalive connections reuse TCP connections, reducing the overhead of opening new ones.

Which directive controls how long nginx keeps an idle keepalive connection open?

A worker_processes

B client_max_body_size

C keepalive_timeout

D proxy_connect_timeout

keepalive_timeout sets the idle time before closing a keepalive connection.

If keepalive is not enabled, what does nginx do after serving a request?

A Keeps the connection open indefinitely

B Closes the connection

C Sends a redirect

D Logs an error

By default, nginx closes the connection after each request unless keepalive is enabled.

Where should the keepalive directive be placed to enable connection reuse to backend servers?

A Inside the upstream block

B Inside the server block

C Inside the location block

D Inside the http block

The keepalive directive must be inside the upstream block to enable reuse of connections to backend servers.

Explain what keepalive connections are in nginx and why they are useful.

Think about how opening new connections affects speed and resources.

Describe how to configure keepalive connections for upstream servers in nginx.

Focus on where and what directives to use.