Am i only using Nginx?

No

• CloudFlare
• Adobe
• NASA
• Netflix
• Dropbox
• Github
• ....[Truncated a very long list]

Lets Dive [nginx open source]

# or any way you like 😛

Master and Worker Processes

• one master and one more more worker
• worker_processes directive in nginx.conf

Controlling NGINX

~ nginx -s SIGNAL_LISTS

• quit
• reload
• stop

~ cat /etc/nginx/nginx.conf

• events - General connection processing
• http - HTTP Traffic
• mail - Mail Traffic
• steam - TCP /UDP Traffic

use : server block

http {
        # Configuration specific to
        # HTTP and affecting all virtual servers
        server {
            # configuration of TCP virtual server 1
        }
        server {
            # configuration of TCP virtual server 2
        }
}
                

~ nginx -s reload

~ nginx -t

Serving static content

server {
        server_name
        listen 80;
        root
        location
}

location /static/ {
        # just do anything ☺️
}
location /media/ {
        # just do anything ☺️
}
                

~ ls /home/static/
     - ok.html

# nginx server block
server  {
    root /home/static/;
    location / {
    }
}

~ curl yourdomain.com/
    - Got a 404 ?

                

server  {
        root /home/static/;
        location / {
           autoindex on;
        }
}
                

Got a auto generated directory listing ? Cool 😎

index to the rescue!!!

server  {
        root /home/static/;
        location / {
              index ok.html;
        }
}
                

server  {
        location /static-root/ {
                root /home/ubuntu/static-root/;
        }
        location /static-alias/ {
                alias /home/ubuntu/static-alias/;
         }
}
                

/static-root/
        - appends the location
        - full path : /home/ubuntu/static-root/static-root/
        - Correct it:
                - root /home/ubuntu/
/static-alias/
        - location parts get dropped
        - full path: /home/ubuntu/static-alias/
        - Bonus:
                Remember the trailing slash on alias

                

server {
    root /home/ubuntu/
    location /images/ {
          try_files $uri /images/default.gif;
    }
}
server {
       root /home/ubuntu/
       location / {
             try_files $uri $uri/ $uri.html =404;
       }
}
                

server {
    location / {
          try_files $uri $uri/ @backend;
     }

    location @backend {
          proxy_pass http://backend.example.com;
    }

}
                

• sends request to specified proxied server
• fetches the response and sends back to client
• Even to non-HTTP servers 😮
• Supported protocols
  • FastCGI
  • uwsgi
  • SCGI
  • memcached
• Use proxy_pass directive

location / {
    proxy_pass http://localhost:8085;
}
                

To pass a request to a non-HTTP proxied server, the appropriate **_pass directive should be used:

• fastcgi_pass passes a request to a FastCGI server
• uwsgi_pass passes a request to a uwsgi server
• scgi_pass passes a request to an SCGI server
• memcached_pass passes a request to a memcached server

• Redefines two header fields
  • Host --> $proxy_host
  • Connection -> close
  Nginx gets rid of any empty headers
• Nginx, by default, will consider any header that contains underscores as invalid
  • use underscores_in_headers directive to “on”

use proxy_set_header

proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header Accept-Encoding "";
                

location / {
     proxy_bind 127.0.0.2;
     proxy_pass http://example.com/;
}

                

Group the servers with upstream directive

upstream backend {
         server backend1.example.com;
         server backend2.example.com;
         server 192.0.0.1;
}
server {
       location / {
           proxy_pass http://backend;
       }
}
            

Load balancing Method

• Round Robin (default)
• Least Connections
  least_conn;
• IP Hash
  • ip_hash;

• Sever weights
  (server backend1.example.com weight=5;)
• Sever Slow -Start
  (server backend1.example.com slow_start=30s;)

Nginx Error Log Severity Levels

- debug - Useful debugging information to help determine where the problem lies.
- info - Informational messages that aren’t necessary to read but may be good to know.
- notice - Something normal happened that is worth noting.
- warn - Something unexpected happened, however is not a cause for concern.
- error - Something was unsuccessful.
- crit - There are problems that need to be critically addressed.
- alert - Prompt action is required.
- emerg - The system is in an unusable state and requires immediate attention.
                

Error Log

• use directive error_log
• defaults to: logs/error.log^*
• eg: error_log logs/error.log alert;
  • will log alert and emerg

Access Logs

• NGINX writes information about client requests in the access log right after the request is processed
• defaults to: logs/access.log^*
• eg: access_log /spool/logs/nginx-access.log;

Log Formats

use directive log_format

                    
log_format compression '$remote_addr - $remote_user [$time_local] '
                        '"$request" $status $body_bytes_sent '
                        '"$http_referer" "$http_user_agent" "$gzip_ratio"';
#Using this compression log format on access_logs
access_log /spool/logs/nginx-access.log compression;

                    
                

You need SSL certificate!!

server {
access_log /home/ubuntu/logs/nginx_access.log;
error_log /home/ubuntu/logs/nginx_error.log;
server_name api.example.com;
location /static/ {
alias /home/ubuntu/static/;
}

if ($host !~* ^(api.example.com)$ ) {
return 444;
}

location / {
.........
proxy_pass http://127.0.0.1:8085;
.........
}

listen 443 ssl;
ssl_certificate SSL_CERTIFICATE_LOCATION;
ssl_certificate_key SSL_CERTIFICATE__KEY_LOCATION;
}
            

server {
    if ($host = api.example.com) {
        return 301 https://$host$request_uri;
    }
	listen 80;
	server_name api.example.com;
    return 404;
}