Code Igniter throwing 404 when trying to access index.php

Question

I used this tutorial to install Enginx, MySQL and PHP: https://www.digitalocean.com/community/tutorials/how-to-install-linux-nginx-mysql-php-lemp-stack-on-ubuntu-14-04

This is my /etc/nginx/sites-available/default file:

# You may add here your
# server {
#   ...
# }
# statements for each of your virtual hosts to this file

##
# 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.
##

server {
    listen 80 default_server;
    listen [::]:80 default_server ipv6only=on;

    root /usr/share/nginx/html;
    index index.php index.html index.htm;

    # Make site accessible from http://localhost/
    server_name localhost;

    location / {
        # First attempt to serve request as file, then
        # as directory, then fall back to displaying a 404.
        try_files $uri $uri/ =404;
        # Uncomment to enable naxsi on this location
        # include /etc/nginx/naxsi.rules
    }

    # Only for nginx-naxsi used with nginx-naxsi-ui : process denied requests
    #location /RequestDenied {
    #   proxy_pass http://127.0.0.1:8080;    
    #}

    error_page 404 /404.html;

    # redirect server error pages to the static page /50x.html
    #
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        root /usr/share/nginx/html;
    }

    # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
    #
    location ~ \.php$ {
        try_files $uri =404;
        fastcgi_split_path_info ^(.+\.php)(/.+)$;
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        fastcgi_index index.php;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include fastcgi_params;
        }
    #   fastcgi_split_path_info ^(.+\.php)(/.+)$;
    #   # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini
    #
    #   # With php5-cgi alone:
    #   fastcgi_pass 127.0.0.1:9000;
    #   # With php5-fpm:
    #   fastcgi_pass unix:/var/run/php5-fpm.sock;
    #   fastcgi_index index.php;
    #   include fastcgi_params;
    #}

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


# another virtual host using mix of IP-, name-, and port-based configuration
#
#server {
#   listen 8000;
#   listen somename:8080;
#   server_name somename alias another.alias;
#   root html;
#   index index.html index.htm;
#
#   location / {
#       try_files $uri $uri/ =404;
#   }
#}


# HTTPS server
#
#server {
#   listen 443;
#   server_name localhost;
#
#   root html;
#   index index.html index.htm;
#
#   ssl on;
#   ssl_certificate cert.pem;
#   ssl_certificate_key cert.key;
#
#   ssl_session_timeout 5m;
#
#   ssl_protocols SSLv3 TLSv1 TLSv1.1 TLSv1.2;
#   ssl_ciphers "HIGH:!aNULL:!MD5 or HIGH:!aNULL:!MD5:!3DES";
#   ssl_prefer_server_ciphers on;
#
#   location / {
#       try_files $uri $uri/ =404;
#   }
#}

I downloaded the CodeIgniter zip folder from here: http://www.codeigniter.com/userguide3/installation/downloads.html and I placed the unzipped folder (CodeIgniter-3.0.0 folder) in /usr/share/nginx/ (Note that for Nginx, the root is set to root /usr/share/nginx/html;.. not sure if it makes a difference or not).

This is my config.php for CodeIgniter:

$config['base_url'] = '127.0.0.1/';
$config['index_page'] = 'index.php';

Now, I'm trying to create a basic static page (following this tutorial: http://www.codeigniter.com/userguide3/tutorial/static_pages.html ).

After I followed the steps above and went to my "Routing" section, it said: The controller is now functioning! Point your browser to [your-site-url]index.php/pages/view to see your page. When you visit index.php/pages/view/about you'll see the about page, again including the header and footer.

However, when I go to 127.0.0.1/index.php, I get a 404 (I also get a 404 if I go to 127.0.0.1/index.php/pages/view).

I think the fact that the /html/ folder and /CodeIgniter-3.0.0/ folder are in the same location might have something to do with it:

/usr/share/nginx/html/
/usr/share/nginx/CodeIgniter-3.0.0/

I'm new to PHP and LEMP. I'm not sure what else information is needed to troubleshoot the issue. Any help is appreciated.

Edit: here is my /usr/share/nginx/CodeIgniter-3.0.0/application/controllers/Pages.php:

<?php
class Pages extends CI_Controller {

    public function view($page = 'home') {

    if (! file_exists(APPPATH.'/views/pages/'.$page.'.php')) {
        show_404();
    }

    $data['title'] = ucfirst($page);
    $this->load->view('templates/header', $data);
    $this->load->view('pages/'.$page, $data);
    $this->load->view('templates/footer', $data);

    }

}

Answer 1

I have the solution. It took two steps:

Step 1) Move the CodeIgniter-3.0.0 folder from

/usr/share/nginx/ 

to

/usr/share/nginx/html/

Step 2) Change

$config['base_url'] = '127.0.0.1/';

to

$config['base_url'] = 'http://localhost/CodeIgniter-3.0.0/';

Now, index.php shows up.