Questions[port-80](server)

NOTE: It turned out that there wasn't any problem at all. See comment for detail.

I've just got fresh instance from Oracle Cloud, Ubuntu 20.04 Minimized. Since I am trying to run DokuWiki on this instance, I've installed these packages:

sudo apt install net-tools lsof wget nano
sudo apt install php7.4-fpm php7.4-xml php7.4-mbstring imagemagick nginx certbot python3-certbot-nginx

I've never touched nginx.conf in /etc/nginx but deleted default symlink in /etc/sites-enabled and put my own conf file in /etc/nginx/conf.d with name example.com.conf(real name is redacted though)

server {
    listen 80 default_server;
    server_name example.com;
    root /var/www/dokuwiki;
    index index.php index.html;

    location / { 
        try_files $uri $uri/ @dokuwiki;
    }

    location @dokuwiki {
        rewrite ^/_media/(.*) /lib/exe/fetch.php?media=$1 last;
        rewrite ^/_detail/(.*) /lib/exe/detail.php?media=$1 last;
        rewrite ^/_export/([^/]+)/(.*) /doku.php?do=export_$1&id=$2 last;
        rewrite ^/(.*) /doku.php?id=$1&$args last;
    }

    location ~ \.php$ {
        include snippets/fastcgi-php.conf;
        fastcgi_pass unix:/var/run/php/php7.4-fpm.sock;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
    }
    
    location ~ /(conf|bin|inc|vendor)/ {
        deny all;
    }
    
    location ~ /data/ {
        internal;
    }
}

and of course, /var/www/dokuwiki is owned by www-data(both user and group) with this command:

sudo chown -R www-data:www-data /var/www/dokuwiki

The problem is, I can't reach to my website. when I type nginx in terminal, it screams like this:

nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx: [emerg] still could not bind()

But, I've checked there is no apache2-like stuff and no other process listening to port 80.

root@redacted:~# lsof -i :80
COMMAND  PID     USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
nginx   1296     root    6u  IPv4  32966      0t0  TCP *:http (LISTEN)
nginx   1297 www-data    6u  IPv4  32966      0t0  TCP *:http (LISTEN)
nginx   1298 www-data    6u  IPv4  32966      0t0  TCP *:http (LISTEN)

root@redacted:~# systemctl status nginx
● nginx.service - A high performance web server and a reverse proxy server
     Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
     Active: active (running) since Sat 2021-11-06 13:24:23 UTC; 16min ago
       Docs: man:nginx(8)
    Process: 1294 ExecStartPre=/usr/sbin/nginx -t -q -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
    Process: 1295 ExecStart=/usr/sbin/nginx -g daemon on; master_process on; (code=exited, status=0/SUCCESS)
   Main PID: 1296 (nginx)
      Tasks: 3 (limit: 1110)
     Memory: 3.1M
     CGroup: /system.slice/nginx.service
             ├─1296 nginx: master process /usr/sbin/nginx -g daemon on; master_process on;
             ├─1297 nginx: worker process
             └─1298 nginx: worker process

Nov 06 13:24:23 redacted systemd[1]: Starting A high performance web server and a reverse proxy server...
Nov 06 13:24:23 redacted systemd[1]: Started A high performance web server and a reverse proxy server.

root@redacted:~# fuser -v 80/tcp
                     USER        PID ACCESS COMMAND
80/tcp:              root       1296 F.... nginx
                     www-data   1297 F.... nginx
                     www-data   1298 F.... nginx

Since I didn't touched nginx.conf, nginx -t is saying that there is no error. but checking .conf file fails:

root@redacted:~# nginx -tc /etc/nginx/conf.d/example.com.conf
nginx: [emerg] "server" directive is not allowed here in /etc/nginx/conf.d/example.com.conf:1
nginx: configuration file /etc/nginx/conf.d/example.com.conf test failed

But I think this isn't relevant of this problem (not sure though).

Even kill all process using port 80 doesn't work neither.

I've searched google for solution of this problem, but haven't found any working one.

PS. I've opened port from iptables and OC web panel. So port thing won't be the reason of this problem I think.

This didn't work for some reason:

server {
    listen       80;
    server_name  localhost;

    location / {
        root   html;
        index  index.html index.htm;
    }
    ...
}

I got

Failed to connect ... port 80: Connection refused

(I tested that nginx was running and port 80 was taken by it)

I then changed listen directive to:

listen [::]:80;

and it worked...

but I have further problems with other servers, for example:

server {
  #listen       80;
  listen [::]:80;
  server_name project.dev;

  location / {
    try_files $uri $uri.html $uri/index.html;
    root /Users/david/project;
    index  index.html index.htm;
  }
}

I put project.dev in /etc/hosts:

127.0.0.1       project.dev

but here I get

curl: (7) Failed to connect to project.dev port 80: Connection refused

no matter what...

I didn't like it that I have to specify ip6 ([::]) in the first place, but now I like it even less because it doesn't even work with other server directives except the main one...

How to get out of this mess?

How to block SKYPE when it's using port 80 & 443 in a network. ( better if I can do it by using ISA 2006 and without disabling web) I know if users can't install skype they wont be able to use it. So without that?

I'm using a fresh install of Centos 5.5. I have Node installed and working (I'm just using Node -- no apache, or nginx.), but I cannot figure out how to make a simple server on port 80. Node is running and is listening to port 80. I'm just using the demo app:

var http = require('http');
http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello World\n');
}).listen(80, "x.x.x.x");
console.log('Server listening to port 80.');

When I visit my IP, it does not work. I obtained my ipaddress using ifconfig. I've tried different ports. So there must be something I am missing.

What do I need to configure on my server to make this work? I would like to do this without installing apache or nginx.

Luke

Edit-- Ok so, I installed nginx and started it up, to see whether or not it is related to node, and I don't see its welcome page. So it definitely has something to do with the server.

Am I retrieving the IP Address correctly by running: ifconfig then reading the inet addr under eth0?

We are running a standalone web server (Windows 2008 + IIS 7), and our antivirus is blocking LSASS.exe (C:\Windows\system32\lsass.exe) from making outbound connections over port 80.

Why is LSASS doing this? (Should I be worried?)