It realy looks like your NGINX ins't running. nginx -s reload is just working if there is a running instance and therfore a PID-file.
Please check the result of the following command.
[root@localhost conf.d]# sudo ps -elf | grep nginx
Should be something like
1 S root 88262 1 0 80 0 - 13143 sigsus 23:47 ? 00:00:00 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf
5 S nginx 88263 88262 0 80 0 - 13257 ep_pol 23:47 ? 00:00:00 nginx: worker process
0 R root 88265 69227 0 80 0 - 28178 - 23:47 pts/1 00:00:00 grep --color=auto nginx
You need at least! the master process and the worker process! If there is no process start your instance by typing
sudo /bin/systemctl start nginx.service OR sudo service nginx start
Check your processlist after running the command.
After you have started the NGINX service there should be PID-file located at
/var/run/nginx.pid and sudo systemctl status nginx.service should printout something like
[root@localhost conf.d]# systemctl status nginx.service
● nginx.service - NGINX Plus - high performance web server
Loaded: loaded (/usr/lib/systemd/system/nginx.service; enabled; vendor preset: disabled)
Active: active (running) since Sat 2020-03-14 23:47:13 EDT; 5min ago
Docs: https://www.nginx.com/resources/
Process: 88232 ExecStop=/bin/kill -s TERM $MAINPID (code=exited, status=0/SUCCESS)
Process: 88260 ExecStart=/usr/sbin/nginx -c /etc/nginx/nginx.conf (code=exited, status=0/SUCCESS)
Process: 88251 ExecStartPre=/usr/libexec/nginx-plus/check-subscription (code=exited, status=0/SUCCESS)
Main PID: 88262 (nginx)
Tasks: 2
Memory: 1.7M
CGroup: /system.slice/nginx.service
├─88262 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf
└─88263 nginx: worker process
Mar 14 23:47:13 localhost.localdomain systemd[1]: Starting NGINX Plus - high performance web server...
Mar 14 23:47:13 localhost.localdomain systemd[1]: Can't open PID file /var/run/nginx.pid (yet?) after start: No such file or directory
Mar 14 23:47:13 localhost.localdomain systemd[1]: Started NGINX Plus - high performance web server.
I am running NGINX Plus but it doesn't matter in this case.