Step‑by‑Step Guide to Install, Configure, and Manage Nginx on CentOS

1. Installation

Download the RPM package, for example

wget http://nginx.org/packages/centos/7/x86_64/RPMS/nginx-1.10.0-1.el7.ngx.x86_64.rpm

, then install it with rpm -ivh nginx-1.10.0-1.el7.ngx.x86_64.rpm. If wget is missing, install it via yum -y install wget.

2. Nginx installation directories

Run whereis nginx to locate files. Typical locations are:

Executable: /usr/sbin/nginx

Modules: /usr/lib64/nginx/modules

Configuration: /etc/nginx/

Default site root: /usr/share/nginx/html

Check the main configuration file and running user with ps aux | grep nginx. The main config file is /etc/nginx/nginx.conf, which defines the PID file, error log, access log, and includes additional files from /etc/nginx/conf.d/.

3. Nginx runtime status

Check status using either: systemctl status nginx.service or service nginx status Running state example:

Stopped state example:

4. Check version

nginx -V

5. Nginx processes

List processes: ps aux | grep nginx # view running processes Filter out the grep itself:

ps aux | grep nginx | grep -v grep   # exclude the grep command

Show listening port (80): netstat -antp | grep :80 or netstat -ntlp | grep :80 Stop Nginx by killing its PID, for example kill -QUIT 2072 for a graceful stop, kill -TERM 2132 for a fast stop, or forcefully with killall -9 nginx or pkill -9 nginx.

6. Verify configuration syntax

Method 1: navigate to the sbin directory and run ./nginx -t.

Successful output shows:

nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful

Method 2: add -t before the -c option in the start command.

7. Restart Nginx

Method 1: run the reload command from the executable directory, e.g., /usr/sbin/nginx -s reload (or the appropriate path for your installation).

Method 2: find the master PID and send a SIGHUP signal: kill -HUP <pid> to trigger a graceful restart.