Created .test.php file with one line of code:
<?php
var_dump(file_get_contents('https://checkip.amazonaws.com'));
?>
When I open .test.php from browser, it shows bool(false) but when I run it from command line, it shows my WAN IP as expected.
php -f .test.php
I am using CentOS 9, nginx 1.20.1, and PHP 8.1.3 (Although I've also tried RHEL8 and Apache)
I tried setting /etc/php-fpm.d/www.conf to use my userid and group to make sure it was not a permission problem.
phpinfo() shows allow_url_fopen is set to On and that curl 7.76.1 is enabled and that OpenSSL is enabled with version 3.0.1
I also tried with an http: URL
I also tried using curl() libraries in the .php file and those fail in the same manner.
Calling exec() from .php file works if it calls php -v or another .php file but not if it calls curl
Not sure what else to try, so I will probably nuke the whole server again.
UPDATE: Found this in /var/log/nginx/error.log
FastCGI sent in stderr: "PHP message: PHP Warning: file_get_contents(https://checkip.amazonaws.com): Failed to open stream: Permission denied
Now what?
Once I found the error log, I was able to find my answer. It was a Linux permission setting and running the following command fixed it:
setsebool -P httpd_can_network_connect on