Hi, I'm having a problem with my forum software. I'm running the latest version. I'm running on nginx with php5-fqm on Ubuntu server. I had this same issue a few weeks ago except the same server was running apache. The problem just "went away" - I can explain it.

What can I do to fix it? What more information can I provide?

Here is a screenshot of the issue:

This is an error message logged by nginx:

PHP message: PHP Notice:  Undefined variable: _SERVER in /var/www/thelonegamers.com/forum/sys/load.php on line 23" while reading response header from upstream, client: 108.162.237.210, server: www.thelonegamers.com, request: "GET /forum/ HTTP/1.1", upstream: "fastcgi://unix:/var/run/php5-fpm.sock:", host: "www.thelonegamers.com", referrer: "http://www.thelonegamers.com/"

Can you try restarting nginx and php ?

I can but I just checked and the problem is gone for now. The server itself, nginx, or php has not been restarted since I had this error last night.

Next time this issue presents itself, I will attempt a restart of both php and nginx. I will bring them both to a complete stop at the same time and restart them.

Problem came back, same as documented in the original post.

There was a system update for Ubuntu today that required a system reboot. I performed the reboot and this resolved the issue with the forum, at least temporarily.

What can I do to make it go away permanently?

Isn't it working properly now after that system update and reboot ?

Let us know if this happens again, we will try to find a permanent solution at that time.

Isn't it working properly now after that system update and reboot ?

Let us know if this happens again, we will try to find a permanent solution at that time.

It works after the system update and reboot. Next time the problem arises, I'll restart nginx and php to confirm that JUST those services restarting resolves the issue.

Isn't it working properly now after that system update and reboot ?

Let us know if this happens again, we will try to find a permanent solution at that time.

I just had this error when logging into the admin panel for my forum but NOT the forum itself. A restart of nginx and php5-fpm resolved the issue, here are the commands I ran on the server for extra clarity:

sudo service nginx stop && sudo service php5-fpm stop
confirmed both were stopped with ps -aux | grep nginx (and then again with php5-fpm)

sudo service nginx start && sudo service php5-fpm start