Ubuntu 20.02 + SSL(Let's Encrypt) 발급 및 설정 (3)

/etc/nginx/sites-available/default

##
# You should look at the following URL's in order to grasp a solid understanding
# of Nginx configuration files in order to fully unleash the power of Nginx.
# https://www.nginx.com/resources/wiki/start/
# https://www.nginx.com/resources/wiki/start/topics/tutorials/config_pitfalls/
# https://wiki.debian.org/Nginx/DirectoryStructure
#
# In most cases, administrators will remove this file from sites-enabled/ and
# leave it as reference inside of sites-available where it will continue to be
# updated by the nginx packaging team.
#
# This file will automatically load configuration files provided by other
# applications, such as Drupal or Wordpress. These applications will be made
# available underneath a path with that package name, such as /drupal8.
#
# Please see /usr/share/doc/nginx-doc/examples/ for more detailed examples.
##

# Default server configuration
#
server {

	# SSL configuration
	#
	# listen 443 ssl default_server;
	# listen [::]:443 ssl default_server;
	#
	# Note: You should disable gzip for SSL traffic.
	# See: https://bugs.debian.org/773332
	#
	# Read up on ssl_ciphers to ensure a secure configuration.
	# See: https://bugs.debian.org/765782
	#
	# Self signed certs generated by the ssl-cert package
	# Don't use them in a production server!
	#
	# include snippets/snakeoil.conf;

	root /var/www/html;

	# Add index.php to the list if you are using PHP
	index index.html index.htm index.nginx-debian.html;

	server_name j9b205.p.ssafy.io;

	location /api {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                # try_files $uri $uri/ =404;
                proxy_pass http://localhost:9090;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header Host $http_host;
  }

	location /ai {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                # try_files $uri $uri/ =404;
                proxy_pass http://localhost:8000;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header Host $http_host;
  }

	location / {
		# First attempt to serve request as file, then
		# as directory, then fall back to displaying a 404.
		# try_files $uri $uri/ =404;
		proxy_pass http://localhost:3000;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header Host $http_host;
	}

	# pass PHP scripts to FastCGI server
	#
	#location ~ \.php$ {
	#	include snippets/fastcgi-php.conf;
	#
	#	# With php-fpm (or other unix sockets):
	#	fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
	#	# With php-cgi (or other tcp sockets):
	#	fastcgi_pass 127.0.0.1:9000;
	#}

	# deny access to .htaccess files, if Apache's document root
	# concurs with nginx's one
	#
	#location ~ /\.ht {
	#	deny all;
	#}

    listen [::]:443 ssl ipv6only=on; # managed by Certbot
    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/j9b205.p.ssafy.io/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/j9b205.p.ssafy.io/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}

# Virtual Host configuration for example.com
#
# You can move that to a different file under sites-available/ and symlink that
# to sites-enabled/ to enable it.
#
#server {
#	listen 80;
#	listen [::]:80;
#
#	server_name example.com;
#
#	root /var/www/example.com;
#	index index.html;
#
#	location / {
#		try_files $uri $uri/ =404;
#	}
#}

server {
    if ($host = j9b205.p.ssafy.io) {
        return 301 https://$host$request_uri;
    } # managed by Certbot

	listen 80 default_server;
	listen [::]:80 default_server;

	server_name j9b205.p.ssafy.io;
    return 404; # managed by Certbot

}

자 일단 이 nginx 설정파일을 한번 뜯어보자.

크게 2개의 서버 블록이 있다.

일단 밑에 있는 작은 server 블록부터 보자

server {
    if ($host = j9b205.p.ssafy.io) {
        return 301 https://$host$request_uri;
    } # managed by Certbot

	listen 80 default_server;
	listen [::]:80 default_server;

	server_name j9b205.p.ssafy.io;
    return 404; # managed by Certbot
}

이 코드를 일목요연하게 설명해보자.

일단 이 서버 블록은 80포트의 요청을 받는다. 근데 80포트는 뭐다? http 요청!!

그래서 이 서버 블록이 의미하는 건

listen 80 default_server;
listen [::]:80 default_server;

server_name j9b205.p.ssafy.io;

우리는 일단 80(http)포트로 오는 요청을 받을꺼야.

그리고 server_name은 j9b205.p.ssafy.io 이거고.

근데 만약에 그 요청을 보낸 host가 j9b205.p.ssafy.io 면??

if ($host = j9b205.p.ssafy.io) {
        return 301 https://$host$request_uri;
} # managed by Certbot

Nginx : “너가 보낸 요청 가지고 그대로 301 리턴할께~ “

근데 301은?? → 리다이렉트 요청!!

말 그대로 “j9b205.p.ssafy.io 로 들어온 http 요청은 https로 바꿔서 그대로 리다이렉트할께!” 를 의미한다.

그러면? 그 다음엔? 다시 리다이렉트했으면 요청이 들어갔겠죠??

어디로??

바로 위에 있는 서버 블록으로!!

왜냐?

server {

	root /var/www/html;

	index index.html index.htm index.nginx-debian.html;

	server_name j9b205.p.ssafy.io;

	location /api {
                proxy_pass http://localhost:9090;
  }

	location /ai {
                proxy_pass http://localhost:8000;
  }

	location / {
				proxy_pass http://localhost:3000;
	}

    listen [::]:443 ssl ipv6only=on; # managed by Certbot
    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/j9b205.p.ssafy.io/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/j9b205.p.ssafy.io/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}

(가독성을 위해 주석처리된 코드는 지웠슴다)

이 코드를 보면 밑에

listen [::]:443 ssl ipv6only=on; # managed by Certbot
listen 443 ssl; # managed by Certbot

이렇게 443(https)포트로 들어오는 요청은 이 서버 블록이 받는다고 나와있으니까!!

그럼 이제 이 서버 블록이 하는 다른 일은 뭘까요

첫번째는 바로

ssl_certificate /etc/letsencrypt/live/j9b205.p.ssafy.io/fullchain.pem; # managed by Certbot
ssl_certificate_key /etc/letsencrypt/live/j9b205.p.ssafy.io/privkey.pem; # managed by Certbot
include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

“letsencrypt에서 발급받는 키를 사용해 SSL 처리도 해줄께!!”

두번째는

location /api {
                proxy_pass http://localhost:9090;
}

location /ai {
                proxy_pass http://localhost:8000;
}

location / {
				proxy_pass http://localhost:3000;
}

이 세가지 location 설정이다.

여기서 각각의 location의 의미는

• location /api는 http://localhost:9090로 리다이렉트 → 여기서 9090은? 백엔드를 의미 → 즉 요청 URI에 /api로 시작한다? → 백엔드 요청이구나! → 바로 백엔드로 요청보냄
• location /ai는 http://localhost:8000로 리다이렉트 → 여기서 8000은? AI 서버(FastAPI)를 의미 → 즉 요청 URI에 /ai로 시작한다? → AI 관련 요청이구나! → 바로 AI 서버로 요청보냄
• location /는 http://localhost:3000로 리다이렉트 → 여기서 3000은? 프론트엔드 서버를 의미 → 요청 URI가 /로 시작한다? → 프론트엔드 요청이구나! → 바로 프론트엔드로 요청보냄

이런 의미이다.