From apache load balancing to nginx load balancing nginx configuration rewrite nginx apache ratio

This is the first time to do load balancing directly like this. The project changed from apache to nginx (Baidu their respective advantages and disadvantages)

Servers: A [Agent], B [tomcat1], C [tomcat2]

1. Eliminate apache Load balancing mode
1. Find the apache installation file, enter the bin directory, stop the httpd service (./httpd -k stop)

2. Modify the server.xml file under tomcat

to

Second, install nginx

...Search on Baidu by yourself

Three, configure nginx load balancing
1. Find the nginx.conf file under nginx and modify it

Completed , start two tomcats, start nginx

502 appears, locate the cause, find the error.log file of nginx (the default path is /var/log/nginx/error.log)

found permission issues

Baidu Finally, it is initially located in the configuration file of nginx.conf

The nginx that appears here may be that the user has insufficient permissions, so change it to root (not necessarily to root, but to a user with permissions)

I found that 502 still appeared. Maybe I still couldn’t find the specific reason. I found this article:

The first solution:

Due to restarting and because I was playing in the test environment, Without restarting, simply proceed to the second solution

setsebool -P httpd_can_network_connect 1

Then access the proxy server address and find that it is successful. At this point, the nginx load balancing is completed

PS: appears Don’t just look at the surface of the problem. I have been looking for the cause of the nginx 502 error online at the beginning. There are a lot of useless things on the Internet. You still need to read more logs to determine where the problem is.

In my humble opinion, God, don’t spray. . . . .

The above has introduced the process from apache load balancing to nginx load balancing, including the content of Apache and nginx. I hope it will be helpful to friends who are interested in PHP tutorials.