Are you stuck with CWP 502 Bad Gateway error? We can help you fix it.

The CentOS Web Panel uses PHP-FPM to serve PHP pages quickly. Often, when PHP-FPM goes down, it throws Bad Gateway errors.

At Bobcares, we help our server owners to fix the CentOS WebPanel errors as part of our Server Management Services.

Today, let’s see what causes the CWP error “502 Bad Gateway” and how our Support Engineers fix it.

Causes of CWP 502 Bad Gateway Error

In general, the CentOS Web Panel shows the 502 error page, when the underlying PHP handler fails to work properly. CWP uses PHP-FPM to process backend data.

PHP-FPM is an advanced and highly-efficient processor for the PHP scripting language. And, as a high-level programming language, PHP scripts require compiling before a web server’s underlying processor hardware can understand it.

Therefore, the PHP-FPM service must run on the same server as the webserver.

And, hence when this PHP-FPM is down, CWP fails in getting results and 502 Bad Gateway error occurs.

How we fix the 502 Bad Gateway Error?

Recently, one of our customers approached us with an error message. He was hitting 502 Bad Gateway errors in his CentOS Web Panel.

And, when this error showed up, he couldn’t log into his CWP admin panel to do any tasks.

Our Support Engineers had a precise look into the error.

We checked whether the status of the service using the below command.

systemctl status cwp-phpfpm

Here, the service was not running and we were not able to start it. Then, we tried to find the User that caused the error by checking the log files.

tail /usr/local/cwp/php71/var/log/php-fpm.log

Here, we got the name of the user that caused the error. For instance, in our case bob.conf created problems.

After that, we deleted the file from /usr/local/cwp/php71/etc/php-fpm.d/users/bob.conf  by running the command,

rm -f /usr/local/cwp/php71/etc/php-fpm.d/users/bob.conf

Finally, we started the PHP-FPM service using the command,

systemctl start cwp-phpfpm

And, this resolved the error.

Restarting the CWP webserver

Similarly, in many cases, restarting the CWP server will also remove the error.

To do so, we run the below command in the command prompt.

sh /scripts/restart_cwpsrv

This restarts the cwpsrv service and makes the panel working again.

[Need more assistance to fix CWP errors? – We’re available 24/7 to help you.]

Conclusion

In short, CWP 502 Bad Gateway error occurs when the PHP script handler PHP-FPM service is down.  In today’s writeup, we discussed how our Support Engineers fixed this error effectively for our customers.