即使仅使用端口80，也无法在Ubuntu的任何端口上启动Nginx

Question

I am unable to start nginx on Ubuntu16.04.

When I run sudo /etc/init.d/nginx start , I get an error.

(env) agaidis@Computer:~$ sudo /etc/init.d/nginx start
[....] Starting nginx (via systemctl): nginx.serviceJob for nginx.service failed because the control process exited with error code. See "systemctl status nginx.service" and "journalctl -xe" for details.
failed!

When I look deeper into the error message by calling,

sudo systemctl status nginx.service

I get the following feedback:

(env) agaidis@Computer:~/www$ sudo systemctl status nginx.service
● nginx.service - A high performance web server and a reverse proxy server
   Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Wed 2017-11-29 01:03:16 EST; 1min 57s ago
  Process: 6887 ExecStart=/usr/sbin/nginx -g daemon on; master_process on; (code=exited, status=1/FAILURE)
  Process: 6883 ExecStartPre=/usr/sbin/nginx -t -q -g daemon on; master_process on; (code=exited, status=0/SUCCESS)

Nov 29 01:03:13 Computer nginx[6887]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
Nov 29 01:03:14 Computer nginx[6887]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
Nov 29 01:03:14 Computer nginx[6887]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
Nov 29 01:03:15 DComputer nginx[6887]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
Nov 29 01:03:15 Computer nginx[6887]: nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
Nov 29 01:03:16 Computer nginx[6887]: nginx: [emerg] still could not bind()
Nov 29 01:03:16 Computer systemd[1]: nginx.service: Control process exited, code=exited status=1
Nov 29 01:03:16 Computer systemd[1]: Failed to start A high performance web server and a reverse proxy server.
Nov 29 01:03:16 Computer systemd[1]: nginx.service: Unit entered failed state.
Nov 29 01:03:16 Computer systemd[1]: nginx.service: Failed with result 'exit-code'.

I have been following the steps on this website to get nginx and gunicorn up a running. I have been looking all over the web for fixes to my problem, but nothing is working.

I have a different server running on port 80 that isn't nginx and so I have switched the ports in my /etc/nginx/sited-available/default , /etc/nginx/sited-available/<name of flask app> , and /etc/nginx/sited-enabled/<name of flask app> all to listen and respond on port 8888. I have tried other port numbers as well. Unfortunately, this doesn't seem to help at all.

My /etc/nginx/sited-available/default file looks like so:

##
# 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.
# http://wiki.nginx.org/Pitfalls
# http://wiki.nginx.org/QuickStart
# http://wiki.nginx.org/Configuration
#
# Generally, you will want to move this file somewhere, and start with a clean
# file but keep this around for reference. Or just disable in sites-enabled.
#
# Please see /usr/share/doc/nginx-doc/examples/ for more detailed examples.
##

# Default server configuration
#
server {
    #listen 8080 default_server;
    listen [::]:8888 ipv6only=on default_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 _;

    location / {
        # First attempt to serve request as file, then
        # as directory, then fall back to displaying a 404.
        try_files $uri $uri/ =404;
    }

    # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
    #
    #location ~ \.php$ {
    #   include snippets/fastcgi-php.conf;
    #
    #   # With php7.0-cgi alone:
    #   fastcgi_pass 127.0.0.1:9000;
    #   # With php7.0-fpm:
    #   fastcgi_pass unix:/run/php/php7.0-fpm.sock;
    #}

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


# 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;
#   }
#}

My /etc/nginx/sited-enabled/<name of flask app> and /etc/nginx/sited-available/<name of flask app> files look like so:

server {
    location / {
        proxy_pass http://localhost:8888;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
    location /static {
        alias /home/agaidis/www/<name of flask app>/static/;
    }
}

Some other things I have tried include sudo apt-get update and sudo apt-get upgrade nginx before I try to start the server.

Is there anyway to fix the problem without stopping the current server running on port 80? Any and all help is greatly appreciated :)

Answer 1

I added listen 8080; to the top of my /etc/nginx/sited-available/<name of flask app> file. Thus, it became:

server {

    listen 8080;

    location / {
        proxy_pass http://localhost:8888;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
    location /static {
        alias /home/agaidis/www/<name of flask app>/static/;
    }
}

That fixed my problem.