Can a software firewall cause issues with Apache, PHP, GD library, or etc?

Question

Hi guys.

A company I am working with recently installed a software firewall on their server. The unfortunate thing is that that coincided with a change that I made to one of their files. But, the only change that I made was a correction to a Smarty template file path inside a script. That's all. The backup file that I made is exactly the same as the new file, except that tiny new change. Now, they are thinking that my change has caused all of these problems. Some of the problems that they are having is the inability to delete images from a web interface, the uploaded images are very pixelated and etc. So, have you guys encountered any issues with firewalls and LAMP?

Thank you!

Answer 1

I would say the easiest thing to do is to revert your changes and see if there problems go away. If you are confident that it is not your change which is causing the issue, and your change was minor then it should be quick to verify and then return your code to its current state.

As to the title of your question, yes it is possible to have a software firewall cause issues with other software on the machine. Generally this is in terms of how the software operates, and some of what you are saying could be because of this. Some of these problems sound like another issue going on, but really there is no way to know without knowing specifics of what has changed.

Again, to rule out your change, just revert, verify that the issue still exists and then move on with troubleshooting from there.