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README

Nginx Admin's Handbook

My notes on NGINX administration basics, tips & tricks, caveats, and gotchas.

^{Hi-diddle-diddle, he played on his
fiddle and danced with lady pigs.
Number three said, "Nicks on tricks!
I'll build my house with EN-jin-EKS!".
The Three Little Pigs: Who's Afraid of the Big Bad Wolf?}

* Nginx official * Nginx distributions * Comparison reviews * Cheatsheets & References * Performance & Hardening * Presentations & Videos * Playgrounds * Config generators * Config parsers * Config managers * Static analyzers * Log analyzers * Performance analyzers * Builder tools * Benchmarking tools * Debugging tools * Security & Web testing tools * Development * Online & Web tools * Other stuff

What's next?

Other chapters

HTTP Basics

* Introduction * Features and architecture * HTTP/2 * How to debug HTTP/2? * HTTP/3 * URI vs URL * Connection vs request * HTTP Headers * Header compression * HTTP Methods * Request * Request line * Methods * Request URI * HTTP version * Request header fields * Message body * Generate requests * Response * Status line * HTTP version * Status codes and reason phrase * Response header fields * Message body * HTTP client * IP address shortcuts * Back-End web architecture * Useful video resources

SSL/TLS Basics

* Introduction * TLS versions * TLS handshake * In which layer is TLS situated within the TCP/IP stack? * RSA and ECC keys/certificates * Cipher suites * Authenticated encryption (AEAD) cipher suites * Why cipher suites are important? * What does insecure, weak, secure and recommended mean? * NGINX and TLS 1.3 Cipher Suites * Diffie-Hellman key exchange * What exactly is the purpose of these DH Parameters? * Certificates * Chain of Trust * What is the main purpose of the Intermediate CA? * Single-domain * Multi-domain * Wildcard * Wildcard SSL doesn't handle root domain? * HTTPS with self-signed certificate vs HTTP * TLS Server Name Indication * Verify your SSL, TLS & Ciphers implementation * Useful video resources

NGINX Basics

* Directories and files * Commands * Processes * CPU pinning * Shutdown of worker processes * Configuration syntax * Comments * End of lines * Variables, Strings, and Quotes * Directives, Blocks, and Contexts * External files * Measurement units * Regular expressions with PCRE * Enable syntax highlighting * Connection processing * Event-Driven architecture * Multiple processes * Simultaneous connections * HTTP Keep-Alive connections * sendfile, tcpnodelay, and tcpnopush * Request processing stages * Server blocks logic * Handle incoming connections * Matching location * rewrite vs return * URL redirections * tryfiles directive * if, break, and set * root vs alias * internal directive * External and internal redirects * allow and deny * uri vs requesturi * Compression and decompression * What is the best NGINX compression gzip level? * Hash tables * Server names hash table * Log files * Conditional logging * Manually log rotation * Error log severity levels * How to log the start time of a request? * How to log the HTTP request body? * NGINX upstream variables returns 2 values * Reverse proxy * Passing requests * Trailing slashes * Passing headers to the backend * Importance of the Host header * Redirects and X-Forwarded-Proto * A warning about the X-Forwarded-For * Improve extensibility with Forwarded * Response headers * Load balancing algorithms * Backend parameters * Upstream servers with SSL * Round Robin * Weighted Round Robin * Least Connections * Weighted Least Connections * IP Hash * Generic Hash * Other methods * Rate limiting * Variables * Directives, keys, and zones * Burst and nodelay parameters * NAXSI Web Application Firewall * OWASP ModSecurity Core Rule Set (CRS) * Core modules * ngxhttpgeomodule * 3rd party modules * ngxsetmisc * ngxhttpgeoipmodule

Helpers

* Installing from prebuilt packages * RHEL7 or CentOS 7 * Debian or Ubuntu * FreeBSD * Installing from source * Automatic installation on RHEL/Debian/BSD * Nginx package * Dependencies * Patches * 3rd party modules * Configure options * Compiler and linker * Debugging Symbols * SystemTap * stapxx * Installation Nginx on CentOS 7 * Pre installation tasks * Dependencies * Get Nginx sources * Download 3rd party modules * Build Nginx * Post installation tasks * Installation OpenResty on CentOS 7 * Installation Tengine on Ubuntu 18.04 * Installation Nginx on FreeBSD 11.3 * Installation Nginx on FreeBSD 11.3 (from ports) * Analyse configuration * Monitoring * GoAccess * Build and install * Analyse log file and enable all recorded statistics * Analyse compressed log file * Analyse log file remotely * Analyse log file and generate html report * Ngxtop * Analyse log file * Analyse log file and print requests with 4xx and 5xx * Analyse log file remotely * Testing * Build OpenSSL 1.0.2-chacha version * Send request and show response headers * Send request with http method, user-agent, follow redirects and show response headers * Send multiple requests * Testing SSL connection * Testing SSL connection (debug mode) * Testing SSL connection with SNI support * Testing SSL connection with specific SSL version * Testing SSL connection with specific cipher * Testing OCSP Stapling * Verify 0-RTT * Testing SCSV * Load testing with ApacheBench (ab) * Standard test * Test with Keep-Alive header * Load testing with wrk2 * Standard scenarios * POST call (with Lua) * Random paths (with Lua) * Multiple paths (with Lua) * Random server address to each thread (with Lua) * Multiple json requests (with Lua) * Debug mode (with Lua) * Analyse data pass to and from the threads * Parsing wrk result and generate report * Load testing with locust * Multiple paths * Multiple paths with different user sessions * TCP SYN flood Denial of Service attack * HTTP Denial of Service attack * Debugging * Show information about processes * Check memory usage * Show open files * Check segmentation fault messages * Dump configuration * Get the list of configure arguments * Check if the module has been compiled * Show the most accessed IP addresses * Show the most accessed IP addresses (ip and url) * Show the most accessed IP addresses (method, code, ip, and url) * Show the top 5 visitors (IP addresses) * Show the most requested urls * Show the most requested urls containing 'string' * Show the most requested urls with http methods * Show the most accessed response codes * Analyse web server log and show only 2xx http codes * Analyse web server log and show only 5xx http codes * Show requests which result 502 and sort them by number per requests by url * Show requests which result 404 for php files and sort them by number per requests by url * Calculating amount of http response codes * Calculating requests per second * Calculating requests per second with IP addresses * Calculating requests per second with IP addresses and urls * Get entries within last n hours * Get entries between two timestamps (range of dates) * Get line rates from web server log * Trace network traffic for all processes * List all files accessed by a NGINX * Check that the gzip_static module is working * Which worker processing current request * Capture only http packets * Extract User Agent from the http packets * Capture only http GET and POST packets * Capture requests and filter by source ip and destination port * Capture HTTP requests/responses in real time, filter by GET, HEAD and save to a file * Dump a process's memory * GNU Debugger (gdb) * Dump configuration from a running process * Show debug log in memory * Core dump backtrace * Debugging socket leaks * Shell aliases * Configuration snippets * Nginx server header removal * Custom log formats * Log only 4xx/5xx * Restricting access with basic authentication * Restricting access with client certificate * Restricting access by geographical location * GeoIP 2 database * Dynamic error pages with SSI * Blocking/allowing IP addresses * Blocking referrer spam * Limiting referrer spam * Blocking User-Agent * Limiting User-Agent * Limiting the rate of requests with burst mode * Limiting the rate of requests with burst mode and nodelay * Limiting the rate of requests per IP with geo and map * Limiting the number of connections * Using trailing slashes * Properly redirect all HTTP requests to HTTPS * Adding and removing the www prefix * Proxy/rewrite and keep the original URL * Proxy/rewrite and keep the part of original URL * Proxy/rewrite without changing the original URL (in browser) * Modify 301/302 response body * Redirect POST request with payload to external endpoint * Route to different backends based on HTTP method * Allow multiple cross-domains using the CORS headers * Set correct scheme passed in X-Forwarded-Proto * Other snippets * Recreate base directory * Create a temporary static backend * Create a temporary static backend with SSL support * Generate password file with htpasswd command * Generate private key without passphrase * Generate private key with passphrase * Remove passphrase from private key * Encrypt existing private key with a passphrase * Generate CSR * Generate CSR (metadata from existing certificate) * Generate CSR with -config param * Generate private key and CSR * List available EC curves * Print ECDSA private and public keys * Generate ECDSA private key * Generate private key and CSR (ECC) * Generate self-signed certificate * Generate self-signed certificate from existing private key * Generate self-signed certificate from existing private key and csr * Generate multidomain certificate (Certbot) * Generate wildcard certificate (Certbot) * Generate certificate with 4096 bit private key (Certbot) * Generate DH public parameters * Display DH public parameters * Extract private key from pfx * Extract private key and certs from pfx * Extract certs from p7b * Convert DER to PEM * Convert PEM to DER * Verification of the certificate's supported purposes * Check private key * Verification of the private key * Get public key from private key * Verification of the public key * Verification of the certificate * Verification of the CSR * Check the private key and the certificate are match * Check the private key and the CSR are match TLSv1.3 and CCM ciphers

Base Rules (16)

* Organising Nginx configuration * Format, prettify and indent your Nginx code * Use reload option to change configurations on the fly * Separate listen directives for 80 and 443 ports * Define the listen directives with address:port pair * Prevent processing requests with undefined server names * Never use a hostname in a listen or upstream directives Set the HTTP headers with addheader and proxy_header directives properly * Use only one SSL config for the listen directive * Use geo/map modules instead of allow/deny * Map all the things... * Set global root directory for unmatched locations * Use return directive for URL redirection (301, 302) * Configure log rotation policy * Use simple custom error pages * Don't duplicate index directive, use it only in the http block

Debugging (5)

* Use custom log formats * Use debug mode to track down unexpected behaviour * Improve debugging by disable daemon, master process, and all workers except one * Use core dumps to figure out why NGINX keep crashing * Use mirror module to copy requests to another backend

Performance (13)

* Adjust worker processes * Use HTTP/2 * Maintaining SSL sessions * Enable OCSP Stapling * Use exact names in a server_name directive if possible * Avoid checks server_name with if directive * Use $request_uri to avoid using regular expressions * Use try_files directive to ensure a file exists * Use return directive instead of rewrite for redirects * Enable PCRE JIT to speed up processing of regular expressions * Activate the cache for connections to upstream servers * Make an exact location match to speed up the selection process * Use limit_conn to improve limiting the download speed

Hardening (31)

* Always keep NGINX up-to-date * Run as an unprivileged user * Disable unnecessary modules * Protect sensitive resources * Take care about your ACL rules * Hide Nginx version number * Hide Nginx server signature * Hide upstream proxy headers * Remove support for legacy and risky HTTP request headers * Use only the latest supported OpenSSL version * Force all connections over TLS * Use min. 2048-bit for RSA and 256-bit for ECC * Keep only TLS 1.3 and TLS 1.2 * Use only strong ciphers * Use more secure ECDH Curve * Use strong Key Exchange with Perfect Forward Secrecy * Prevent Replay Attacks on Zero Round-Trip Time * Defend against the BEAST attack * Mitigation of CRIME/BREACH attacks * Enable HTTP Strict Transport Security * Reduce XSS risks (Content-Security-Policy) * Control the behaviour of the Referer header (Referrer-Policy) * Provide clickjacking protection (X-Frame-Options) * Prevent some categories of XSS attacks (X-XSS-Protection) * Prevent Sniff Mimetype middleware (X-Content-Type-Options) * Deny the use of browser features (Feature-Policy) * Reject unsafe HTTP methods * Prevent caching of sensitive data * Limit concurrent connections * Control Buffer Overflow attacks * Mitigating Slow HTTP DoS attacks (Closing Slow Connections)

Reverse Proxy (8)

* Use pass directive compatible with backend protocol * Be careful with trailing slashes in proxy_pass directive * Set and pass Host header only with $host variable * Set properly values of the X-Forwarded-For header * Don't use X-Forwarded-Proto with $scheme behind reverse proxy * Always pass Host, X-Real-IP, and X-Forwarded headers to the backend * Use custom headers without X- prefix * Always use $requesturi instead of $uri in proxy_pass

Load Balancing (2)

* Tweak passive health checks * Don't disable backends by comments, use down parameter

Others (4)

* Set the certificate chain correctly * Enable DNS CAA Policy * Define security policies with security.txt * Use tcpdump to diagnose and troubleshoot the HTTP issues

Configuration Examples

* Reverse Proxy * Installation * Configuration * Import configuration * Set bind IP address * Set your domain name * Regenerate private keys and certs * Update modules list * Generating the necessary error pages * Add new domain * Test your configuration

Introduction

> Before you start playing with NGINX please read an official Beginner’s Guide. It's a great introduction for everyone.

Nginx (/ˌɛndʒɪnˈɛks/ EN-jin-EKS, stylized as NGINX or nginx) is an open source HTTP and reverse proxy server, a mail proxy server, and a generic TCP/UDP proxy server with a strong focus on high concurrency, performance and low memory usage. It is originally written by Igor Sysoev.

For a long time, it has been running on many heavily loaded Russian sites including Yandex, Mail.Ru, VK, and Rambler. At this moment some high-profile companies using NGINX include Cisco, DuckDuckGo, Facebook, GitLab, Google, Twitter, Apple, Intel, and many more. In the September 2019 it was the most commonly used HTTP server (see Netcraft survey).

NGINX is a fast, light-weight and powerful web server that can also be used as a:

fast HTTP reverse proxy
reliable load balancer
high performance caching server
full-fledged web platform

So, to be brief, it provides the core of complete web stacks and is designed to help build scalable web applications. When it comes to performance, NGINX can easily handle a huge amount of traffic. The other main advantage of the NGINX is that allows you to do the same thing in different ways.

Unlike traditional HTTP servers, NGINX doesn't rely on threads to handle requests and it was written with a different architecture in mind - one which is much more suitable for nonlinear scalability in both the number of simultaneous connections and requests per second.

NGINX is also known as a Apache Killer (mainly because of its lightness and much less RAM consumption). It is event-based, so it does not follow Apache's style of spawning new processes or threads for each web page request. Generally, it was created to solve the C10K problem.

For me, it is a one of the best and most important service that I used in my SysAdmin career.

These essential documents should be the main source of knowledge for you:

In addition, I would like to recommend three great docs focuses on the concept of the HTTP protocol:

If you love security keep your eye on this one: Cryptology ePrint Archive. It provides access to recent research in cryptology and explores many subjects of security (e.g. Ciphers, Algorithms, SSL/TLS protocols). A great introduction that covers core concepts of cryptography is Practical Cryptography for Developers. I also recommend to read the Bulletproof SSL and TLS. Yep, it's definitely the most comprehensive book about deploying TLS for me.

An obligatory source of knowledge is also the OWASP Cheat Sheet Series. You should ought treat it as an excellent security guidance. Burp Scanner - Issue Definitions introduces you to the web apps and security vulnerabilities. Finally, The Web Security Academy is a free online training center for web application security with high-quality reading materials and interactive labs of varying levels of difficulty. All are really good source to start learning about web application security.

And, of course, always browse official Nginx Security Advisories and CVE databases like CVE Details or CVE - The MITRE Corporation - to stay Up-to-Date on NGINX vulnerabilities.

Prologue

When I was studying architecture of HTTP servers I became interested in NGINX. As I was going through research, I kept notes. I found a lot of information about it, e.g. forum posts on the web about every conceivable problem was great. However, I've never found one guide that covers the most important things in a suitable form. I was a little disappointed.

I was interested in everything: NGINX internals, functions, security best practices, performance optimisations, tips & tricks, hacks and rules, but for me some of the documents treated the subject lightly.

Of course, NGINX Official Documentation is the best place but I know that we also have other great resources:

These are definitely the best assets for us and in the first place you should seek help there. Moreover, in order to improve your knowledge, please see Books chapter - it contains top literature on NGINX.

Why I created this handbook

For me, however, there hasn't been a truly in-depth and reasonably simple cheatsheet which describe a variety of configurations and important cross-cutting topics for HTTP servers. Configuration of the NGINX can be tricky sometimes and you really need to get into the syntax and concepts to get an understanding tricks, loopholes, and mechanisms. The documentation isn't as pretty as other projects and should certainly include more robust examples.

> This handbook is a set of rules and recommendations for the NGINX Open Source HTTP server. It also contains the best practices, notes, and helpers with countless examples. Many of them refer to external resources.

There are a lot of things you can do to improve in your NGINX instance and this guide will attempt to cover as many of them as possible. For the most part, it contains the most important things about NGINX for me. I think the configuration you provided should work without any talisman. That's why I created this repository.

With this handbook you will explore the many features and capabilities of the NGINX. You'll find out, for example, how to testing the performance or how to resolve debugging problems. You will learn configuration guidelines, security design patterns, ways to handle common issues and how to stay out of them. I explained here a few best tips to avoid pitfalls and configuration mistakes.

I added set of guidelines and examples has also been produced to help you administer of the NGINX. They give us insight into NGINX internals also.

Mostly, I apply the rules presented here on the NGINX working as a reverse proxy. However, does not to prevent them being implemented for NGINX as a standalone server.

Who this handbook is for

If you do not have the time to read hundreds of articles (just like me) this multipurpose handbook may be useful. I created it in the hope that it will be useful especially for System Administrators and Experts of Web-based applications.

This handbook does not get into all aspects of NGINX. What's more, some of the things described in this guide may be rather basic because most of us do not configure NGINX every day and it is easy to forget about basic/trivial things. On the other hand, also discusses heavyweight topics so there is something for advanced users. I tried to put external resources in many places in this handbook in order to dispel any suspicion that may exist.

I did my best to make this handbook a single and consistent (but now I know that is really hard). It's organized in an order that makes logical sense to me. I think it can also be a good complement to official documentation and other great documents. Many of the topics described here can certainly be done better or different. Of course, I still have a lot to improve and to do. I hope you enjoy and have fun with it.

Do not treat this handbook and notes written here as revealed knowledge. You should take a scientific approach when reading this document. If you have any doubts and disagree with me, please point out my mistakes. You should to discover cause and effect relationships by asking questions, carefully gathering and examining the evidence, and seeing if all the available information can be combined in to a logical answer.

I create this handbook for one more reason. Rather than starting from scratch in, I putting together a plan for answering your questions to help you find the best way to do things and ensure that you don't repeat my mistakes from the past.

So, what's most important:

ask a questions about something that you observe
do background research
do tests with an experiments
analyze and draw conclusions
communicate results (for us!)

Finally, you should know I'm not a NGINX expert but I love to know how stuff works and why work the way they do. I’m not a crypto expert... but I do know the term "elliptic curve" (I really like this quote!). Don't need to be an expert to figure out the reason just got to have used this and not this or why something works this way and not another. It feels good to understand the recommendations and nuances of a topic you’re passionate about.

Before you start

Remember about the following most important things:

> Blindly deploying of the rules described here can damage your web application!

> Do not follow guides just to get 100% of something. Think about what you actually do at your server!

> Copy-and-paste is not the best way to learn. Think twice before adopting rules from this handbook.

> There are no settings that are perfect for everyone.

> Always think about what is better and more important for you: security vs usability/compatibility.

> Security mainly refers to minimise the risk.

> Change one thing may open a whole new set of problems.

> Read about how things work and what values are considered secure enough (and for what purposes).

> The only correct approach is to understand your exposure, measure and tune.

+ Security is important for ethical reasons. Compliance is important for legal reasons.
The key to workplace contentment is understanding they are unrelated to each other.
Both are important, but one does not lead to the other (compliance != security).
author: unknown
Security is always needed, no matter what type of website it is. It can be static HTML
or fully dynamic, an attacker can still inject hostile content into the page in transit
to attack the user.
author: Scott Helme
Don’t enable older deprecated protocols just because Karen in Florida is still using
a PC that she bought back in 2001.
author: thisinterestsmeblog

I think, in the age of phishing, cyber attacks, ransomware, etc., you should take care of security of your infrastructure as hard as possible but don't ever forget about this one...

Lastly, I would like to quote two very important comments found on the web about compliance with the standards and regulations, and essence of a human factor in security:

> Regulations that make sense are often not descriptive - capturing the intent and scope of a rule often requires technical expertise. More than that, it's the type of expertise most organisations do not have. And instead of improving themselves, these companies, who may form the grand majority of the industry, petition the regulators to provide a safe checklist of technical mitigations that can be implemented to remain compliant. [...] Instead of doing the right thing and meeting the planned intent, companies are instead ticking nonsensical boxes that the regulators and their auditors demand. Blindly. Mindlessly. Divorced from reality. - by bostik

> Whenever considering security, the human factor is nearly always as important or more important than just the technical aspects. Policy and procedures need to consider the human element and try to ensure that these policies and procedures are structured in such a way as to help enable staff to do the right thing, even when they may not fully understand why they need to do it. - by Tim X

Contributing & Support

> A real community, however, exists only when its members interact in a meaningful way that deepens their understanding of each other and leads to learning.

If you find something which doesn't make sense, or something doesn't seem right, please make a pull request and please add valid and well-reasoned explanations about your changes or comments.

Before adding a pull request, please see the contributing guidelines.

Code Contributors

This project exists thanks to all the people who contribute.

ToDo

What needs to be done? Look at the following ToDo list:

New chapters:

[x] Bonus Stuff
[x] HTTP Basics
[x] SSL/TLS Basics
[x] Reverse Proxy
[ ] Caching
[x] Core modules
[x] 3rd party modules
[ ] Web Application Firewall
[ ] ModSecurity
[x] Debugging

Existing chapters:

Introduction

- [x] Prologue - [x] Why I created this handbook - [x] Who this handbook is for - [x] Before you start - [x] Contributing & Support - [x] _RSS Feed & Updates - [x] Checklist to rule them all

Bonus Stuff

- [x] Fully automatic installation - [x] Static error pages generator - [x] Server names parser

Books

- [x] ModSecurity 3.0 and NGINX: Quick Start Guide - [x] Cisco ACE to NGINX: Migration Guide

External Resources

- Nginx official - [x] Nginx Forum - [x] Nginx Mailing List - [x] NGINX-Demos - Presentations & Videos - [x] NGINX: Basics and Best Practices - [x] NGINX Installation and Tuning - [x] Nginx Internals (by Joshua Zhu) - [x] Nginx internals (by Liqiang Xu) - [x] How to secure your web applications with NGINX - [x] Tuning TCP and NGINX on EC2 - [x] Extending functionality in nginx, with modules! - [x] Nginx - Tips and Tricks. - [x] Nginx Scripting - Extending Nginx Functionalities with Lua - [x] How to handle over 1,200,000 HTTPS Reqs/Min - [x] Using ngxlua / lua-nginx-module in pixiv_ - Cheatsheets & References - [x] Nginx configurations for most popular CMS/CMF/Frameworks based on PHP - Performance & Hardening - [x] Memorable site for testing clients against bad SSL configs - Config parsers - [x] Quick and reliable way to convert NGINX configurations into JSON and back - [x] Parses nginx configuration with Pyparsing - Config managers - [x] Ansible role to install and manage nginx configuration - [x] Ansible Role - Nginx - [x] Ansible role for NGINX - [x] Puppet Module to manage NGINX on various UNIXes - Static analyzers - [x] nginx-minify-conf - Comparison reviews - [x] NGINX vs. Apache (Pro/Con Review, Uses, & Hosting for Each) - [x] Web cache server performance benchmark: nuster vs nginx vs varnish vs squid - Builder tools - [x] Nginx-builder - Benchmarking tools - [x] wrk2 - [x] httperf - [x] slowloris - [x] slowhttptest - [x] GoldenEye - Debugging tools - [x] strace - [x] GDB - [x] SystemTap - [x] stapxx - [x] htrace.sh - Security & Web testing tools - [x] Burp Suite - [x] w3af - [x] nikto - [x] ssllabs-scan - [x] http-observatory - [x] testssl.sh - [x] sslyze - [x] cipherscan - [x] O-Saft - [x] Nghttp2 - [x] h2spec - [x] http2fuzz - [x] Arjun - [x] Corsy - [x] XSStrike - Online & Web tools - [x] ssltools - Other stuff - [x] OWASP Cheat Sheet Series - [x] Mozilla Web Security - [x] Application Security Wiki - [x] OWASP ASVS 4.0 - [x] The System Design Primer - [x] awesome-scalability - [x] Web Architecture 101

HTTP Basics

- [x] Features and architecture - [x] HTTP/2 - [x] How to debug HTTP/2? - [x] HTTP/3 - [x] URI vs URL - [x] Connection vs request - [x] HTTP Headers - [x] Header compression - [x] HTTP Methods - [x] Request - [x] Request line - [x] Methods - [x] Request URI - [x] HTTP version - [x] Request header fields - [x] Message body - [x] Generate requests - [x] Response - [x] Status line - [x] HTTP version - [x] Status codes and reason phrase - [x] Response header fields - [x] Message body - [x] HTTP client - [x] IP address shortcuts - [x] Back-End web architecture - [x] Useful video resources

SSL/TLS Basics

- [x] TLS versions - [x] TLS handshake - [x] In which layer is TLS situated within the TCP/IP stack? - [x] RSA and ECC keys/certificates - [x] Cipher suites - [x] Authenticated encryption (AEAD) cipher suites - [x] Why cipher suites are important? - [x] NGINX and TLS 1.3 Cipher Suites - [x] Diffie-Hellman key exchange - [x] Certificates - [x] Chain of Trust - [x] What is the main purpose of the Intermediate CA? - [x] Single-domain - [x] Multi-domain - [x] Wildcard - [x] Wildcard SSL doesn't handle root domain? - [x] TLS Server Name Indication - [x] Verify your SSL, TLS & Ciphers implementation - [x] Useful video resources

NGINX Basics

- Processes - [x] CPU pinning - [x] Shutdown of worker processes - Configuration syntax - [x] Comments - [x] End of lines - [x] Variables, Strings, and Quotes - [x] Directives, Blocks, and Contexts - [x] External files - [x] Measurement units - [x] Regular expressions with PCRE - [x] Enable syntax highlighting - Connection processing - [x] Event-Driven architecture - [x] Multiple processes - [x] Simultaneous connections - [x] HTTP Keep-Alive connections - [x] sendfile, tcpnodelay, and tcpnopush - Server blocks logic - [x] Matching location - [ ] if in location - [ ] Nested locations - [x] rewrite vs return - [x] tryfiles directive_ - [x] if, break and set - [x] root vs alias - [x] internal directive - x