Nginx
nginx is a robust, small, high performance web server and reverse proxy server. It is a good alternative to popular web servers like Apache and lighttpd.
Installation[edit | edit source]
Before immediately installing the www-servers/nginx package, first take a good look at the USE flags for Nginx.
Expanded USE flags[edit | edit source]
Nginx uses modules to enhance its features. To simplify the maintenance of this modular approach, the nginx ebuild uses expanded USE (USE_EXPAND) flags to denote which modules should be installed.
- HTTP related modules can be enabled through the NGINX_MODULES_HTTP variable
- Mail related modules can be enabled through the NGINX_MODULES_MAIL variable
- Third party modules can be enabled through the NGINX_ADD_MODULES variable
These variables need to be set in /etc/portage/make.conf. Their descriptions can be found in /var/db/repos/gentoo/profiles/desc/nginx_modules_http.desc and /var/db/repos/gentoo/profiles/desc/nginx_modules_mail.desc.
For example, to enable the fastcgi
module:
/etc/portage/make.conf
NGINX_MODULES_HTTP="fastcgi"
The above will overwrite the default value of NGINX_MODULES_HTTP and set it to fastcgi
. To enable the fastcgi
module without overwriting the default NGINX_MODULES_HTTP value, the following USE flag notation can be specified in /etc/portage/package.use:
/etc/portage/package.use
www-servers/nginx NGINX_MODULES_HTTP: fastcgi
USE flags[edit | edit source]
USE flags for www-servers/nginx Robust, small and high performance http and reverse proxy server
aio
|
Enables file AIO support |
debug
|
Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see https://wiki.gentoo.org/wiki/Project:Quality_Assurance/Backtraces |
http
|
Enable HTTP core support |
http-cache
|
Enable HTTP cache support |
http2
|
Enable HTTP2 module support |
ipv6
|
Add support for IP version 6 |
libatomic
|
Use libatomic instead of builtin atomic operations |
libressl
|
Use dev-libs/libressl instead of dev-libs/openssl when applicable (see also the ssl useflag) |
pcre
|
Add support for Perl Compatible Regular Expressions |
pcre-jit
|
Enable JIT for pcre |
rtmp
|
NGINX-based Media Streaming Server |
selinux
|
!!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur |
ssl
|
Enable HTTPS module for http. Enable SSL/TLS support for POP3/IMAP/SMTP for mail. |
threads
|
Add threads support for various packages. Usually pthreads |
vim-syntax
|
Pulls in related vim syntax scripts |
Emerge[edit | edit source]
With the USE flags set, install www-servers/nginx:
root #
emerge --ask www-servers/nginx
Installation verification[edit | edit source]
The default nginx configuration defines a virtual server with the root directory set to /var/www/localhost/htdocs. However due to bug #449136, the nginx ebuild will only create the /var/www/localhost directory and without an index file. To have a working default configuration, create the /var/www/localhost/htdocs directory and simple index file:
root #
mkdir /var/www/localhost/htdocs
root #
echo 'Hello, world!' > /var/www/localhost/htdocs/index.html
The nginx package installs an init service script allowing administrators to stop, start, or restart the service. Run the next command to start the nginx service:
root #
/etc/init.d/nginx start
To verify that nginx is properly running, point a web browser to the http://localhost address or use a command-line web tool like curl:
user $
curl http://localhost
Configuration[edit | edit source]
The nginx configuration is handled through the /etc/nginx/nginx.conf file.
Single site access[edit | edit source]
The following example shows a single-site access, without dynamic capabilities (such as PHP).
/etc/nginx/nginx.conf
Gentoo's default configurationuser nginx nginx; worker_processes 1; error_log /var/log/nginx/error_log info; events { worker_connections 1024; use epoll; } http { include /etc/nginx/mime.types; default_type application/octet-stream; log_format main '$remote_addr - $remote_user [$time_local] ' '"$request" $status $bytes_sent ' '"$http_referer" "$http_user_agent" ' '"$gzip_ratio"'; client_header_timeout 10m; client_body_timeout 10m; send_timeout 10m; connection_pool_size 256; client_header_buffer_size 1k; large_client_header_buffers 4 2k; request_pool_size 4k; gzip off; output_buffers 1 32k; postpone_output 1460; sendfile on; tcp_nopush on; tcp_nodelay on; keepalive_timeout 75 20; ignore_invalid_headers on; index index.html; server { listen 127.0.0.1; server_name localhost; access_log /var/log/nginx/localhost.access_log main; error_log /var/log/nginx/localhost.error_log info; root /var/www/localhost/htdocs; } }
Multiple site access[edit | edit source]
It is possible to leverage the include
directive to split the configuration in multiple files:
/etc/nginx/nginx.conf
Multisite configurationuser nginx nginx; worker_processes 1; error_log /var/log/nginx/error_log info; events { worker_connections 1024; use epoll; } http { include /etc/nginx/mime.types; default_type application/octet-stream; log_format main '$remote_addr - $remote_user [$time_local] ' '"$request" $status $bytes_sent ' '"$http_referer" "$http_user_agent" ' '"$gzip_ratio"'; client_header_timeout 10m; client_body_timeout 10m; send_timeout 10m; connection_pool_size 256; client_header_buffer_size 1k; large_client_header_buffers 4 2k; request_pool_size 4k; gzip off; output_buffers 1 32k; postpone_output 1460; sendfile on; tcp_nopush on; tcp_nodelay on; keepalive_timeout 75 20; ignore_invalid_headers on; index index.html; include /etc/nginx/conf.d/*.conf; }
/etc/nginx/conf.d/local.conf
Simple hostserver { listen 127.0.0.1; server_name localhost; access_log /var/log/nginx/localhost.access_log main; error_log /var/log/nginx/localhost.error_log info; root /var/www/localhost/htdocs; }
/etc/nginx/conf.d/local-ssl.conf
Simple SSL hostserver { listen 443 ssl; server_name host.tld; ssl_certificate /etc/ssl/nginx/host.tld.pem; ssl_certificate_key /etc/ssl/nginx/host.tld.key; }
PHP support[edit | edit source]
Add the following lines to the nginx configuration to enable PHP support. In this example nginx is exchanging information with the PHP process via a UNIX socket.
/etc/nginx/nginx.conf
Enabling PHP support... http { ... server { ... location ~ \.php$ { # Test for non-existent scripts or throw a 404 error # Without this line, nginx will blindly send any request ending in .php to php-fpm try_files $uri =404; include /etc/nginx/fastcgi.conf; fastcgi_pass unix:/run/php-fpm.socket; } } }
To support this setup, PHP needs to be built with FastCGI Process Manager support (dev-lang/php), which is handled through the fpm
USE flag:
root #
echo "dev-lang/php fpm" >> /etc/portage/package.use
Rebuild PHP with the fpm
USE flag enabled:
root #
emerge --ask dev-lang/php
Using UNIX socket communication is the preferred and recommended configuration
For PHP 7.0 and newer PHP versions use following configuration:
/etc/php/fpm-php7.1/fpm.d/www.conf
Running PHP with UNIX socket supportlisten = /run/php-fpm.socket listen.owner = nginx
Set the timezone in the php-fpm php.ini file. Substitute the <PUT_TIMEZONE_HERE>
text in the FileBox below with the appropriate timezone information:
/etc/php/fpm-php5.5/php.ini
Setup timezone in php.inidate.timezone = <PUT_TIMEZONE_HERE>
Start the php-fpm daemon:
root #
/etc/init.d/php-fpm start
Add php-fpm to the default runlevel:
root #
rc-update add php-fpm default
Reload nginx with changed configuration:
root #
/etc/init.d/nginx reload
Alternatively, for systemd:
root #
systemctl enable php-fpm@7.1
root #
systemctl start php-fpm@7.1
IP address access list[edit | edit source]
The next example shows how to allow access to a particular URL (in this case /nginx_status) only to:
- certain hosts (e.g. 192.0.2.1 127.0.0.1)
- and IP networks (e.g. 198.51.100.0/24)
/etc/nginx/nginx.conf
Enabling and configuring an IP access lists for /nginx_status pagehttp { server { location /nginx_status { stub_status on; allow 127.0.0.1/32; allow 192.0.2.1/32; allow 198.51.100.0/24; deny all; } } }
Basic authentication[edit | edit source]
nginx allows limiting access to resources by validating the user name and password:
/etc/nginx/nginx.conf
Enabling and configuring user authentication for the / locationhttp { server { location / { auth_basic "Authentication failed"; auth_basic_user_file conf/htpasswd; } } }
The htpasswd file can be generated using:
user $
openssl passwd
Third party modules[edit | edit source]
Download third party module source and move it to /usr/src. Manually compile the selected Nginx module, then add the following line to /etc/portage/make.conf:
/etc/portage/make.conf
Adding third party moduleNGINX_ADD_MODULES="/usr/src/nginxmodule"
Rebuild nginx with the third party module enabled:
root #
emerge --ask www-servers/nginx
Usage[edit | edit source]
Service control[edit | edit source]
OpenRC[edit | edit source]
Start nginx web server:
root #
rc-service nginx start
Stop nginx web server:
root #
rc-service nginx stop
Add nginx to the default runlevel so that the service starts automatically on system reboot:
root #
rc-update add nginx default
Reload nginx configuration without dropping connections:
root #
rc-service nginx reload
Restart the nginx service:
root #
rc-service nginx restart
systemd[edit | edit source]
Start nginx web server:
root #
systemctl start nginx
Stop nginx web server:
root #
systemctl stop nginx
Check the status of the service:
root #
systemctl status nginx
Enable service to start automatically on system reboot:
root #
systemctl enable nginx
Reload nginx configuration without dropping connections:
root #
systemctl reload nginx
Restart the nginx service:
root #
systemctl restart nginx
Troubleshooting[edit | edit source]
In case of problems, the following commands can help troubleshoot the situation.
Validate configuration[edit | edit source]
Verify that the running nginx configuration has no errors:
root #
/usr/sbin/nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok nginx: configuration file /etc/nginx/nginx.conf test is successful
By running nginx with the -t
option, it will validate the configuration file without actually starting the nginx daemon. Use the -c
option with the full path to the file to test configuration files in non-default locations.
Verify processes are running[edit | edit source]
Check if nginx processes are running:
user $
ps aux | egrep 'nginx|PID'
PID TTY STAT TIME COMMAND 26092 ? Ss 0:00 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf 26093 ? S 0:00 nginx: worker proces
Verify bound addresses and ports[edit | edit source]
Verify nginx daemon is listening on the right TCP port (such as 80 for HTTP or 443 for HTTPS):
root #
netstat -tulpen | grep :80
tcp 0 0 127.0.0.1:80 0.0.0.0:* LISTEN 0 12336835 -26092/nginx: master
See also[edit | edit source]
- Apache — an efficient, extensible web server. It is one of the most popular web servers used the Internet.
- Lighttpd — a fast and lightweight web server.
External resources[edit | edit source]
- https://nginx.org/en/docs/beginners_guide.html - A nginx beginner's guide. Helpful for those who do not know much about nginx.
- https://nginx.com/resources/admin-guide/ - The ngnix administration guide. Helpful for web administrators who have been working in the field.
- http://wiki.nginx.org/Main - The nginx wiki.
- https://github.com/h5bp/server-configs-nginx - H5BP nginx config.