Can my nginx configurations work without default server - nginx

Question

I have five domains i am trying to setup on nginx installation
This is what i found as default conf
##
# 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 {
listen 80 default_server;
listen [::]:80 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 $uri/ =404;
}
# pass PHP scripts to FastCGI server
#
#location ~ \.php$ {
# include snippets/fastcgi-php.conf;
#
# # With php-fpm (or other unix sockets):
# fastcgi_pass unix:/var/run/php/php7.0-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;
#}
}
# 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;
# }
#}
I want to remove the comments and default conf and replace it with numbered conf files like
server {
listen 80 default_server;
listen [::]:80 default_server ipv6only=on;
server_name first.com www.first.com;
root /var/www/first;
index index.html;
location / {
try_files $uri $uri/ =404;
}
}
one.conf and two.conf
server {
listen 80;
listen [::]:80;
server_name second.com www.second.com;
root /var/www/second;
index index.html;
location / {
try_files $uri $uri/ =404;
}
}
Granted i delete the default conf, what is the effect of leaving out default_server in the one.conf conf?
Thanks.

Answer 1

Nginx always has a default server. It is either the one you choose with the default_server attribute, otherwise Nginx will use the first server block with the correct listen directive. See this document for details.
In your case, the first server block will be in the first .conf file, which is usually the one with the first filename when sorted alphanumerically.