How To Disable SELinux on CentOS 7 | Darren's Tech Tutorials

Stop SELinux Errors! The Permanent Guide to Disabling SELinux on CentOS 7

Hi everyone, and welcome back to Darren’s Tech Tutorials!

If you’ve spent any time working on CentOS, Red Hat, or Fedora, you’ve probably run into the frustrating roadblock known as SELinux. It’s a powerful security layer, but sometimes it’s just plain overkill, turning simple installations of tools like WordPress, Moodle, or ownCloud into a stressful debugging nightmare.

We’ve all been there: you follow a tutorial perfectly, only to be met with a generic error screen after the install. Nine times out of ten, SELinux is the culprit.

While strong security is crucial, if you’re already managing security through robust firewalls (like iptables or firewalld), temporarily disabling or permanently turning off SELinux can save you a huge headache.

In this comprehensive guide, we’re going to permanently disable SELinux on CentOS 7 in just a few simple steps.

What Exactly is SELinux and Why Disable It?

SELinux (Security-Enhanced Linux) is a Linux kernel security module that provides access control security policies. Essentially, it controls what processes and users can access files, directories, and ports.

While this sounds great in theory, when you install new web applications (especially older or non-standard ones), SELinux often blocks the necessary read/write permissions, resulting in the dreaded “permission denied” or “access forbidden” errors, even if your file permissions (chmod/chown) look correct.

For most personal lab environments or environments where other security layers are active, temporarily disabling SELinux is a standard practice to ensure compatibility.

Step 1: Temporarily Disabling SELinux

Before we commit to a permanent change, it’s often useful to check if SELinux is even the cause of your installation errors. We can temporarily disable it using the setenforce command.

Important: This change will revert upon reboot. Use this only for quick testing!

Open your terminal and execute the following command:

sudo setenforce 0

Once executed, check your application again. If the error is gone (for example, your ownCloud installation page loads successfully!), you know SELinux was the problem. If you reboot now, SELinux will re-enable itself, meaning we need to move to the permanent configuration change.

Step 2: Permanently Disabling SELinux via Configuration File

To ensure SELinux stays disabled even after a system reboot, we need to edit the main configuration file located in /etc/sysconfig/selinux.

We will use the vi editor for this task:

sudo vi /etc/sysconfig/selinux

Once the file opens, you will see configuration settings that look something like this:

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
# enforcing - SELinux security policy is enforced.
# permissive - SELinux prints warnings instead of enforcing.
# disabled - No SELinux policy is loaded.
SELINUX=enforcing

We need to change the line SELINUX=enforcing to SELINUX=disabled.

Editing Instructions (Using VI):

Press the letter i to enter Insert Mode.
Navigate down to the line starting with SELINUX= and change the value:
```
SELINUX=disabled
```
Press the Esc key to exit Insert Mode.
Type :wq (write and quit) and press Enter.

Step 3: Applying the Changes (System Reboot Required)

Unlike some configuration files, the SELinux setting change will not take effect immediately. You must reboot the CentOS system to load the new kernel parameters.

Use the following command to reboot your system:

sudo init 6

Your system will now restart. Give it a minute or two to boot back up.

Verification

Once your system is back online, open your web browser or application again. You should find that those pesky permission errors are completely gone!

We’ve successfully disabled SELinux, guaranteeing a smoother experience for all your future installations on this server.

Final Thoughts

It feels great to finally conquer those stubborn security errors! Disabling SELinux is a fantastic workaround when you know your environment is protected by other robust security measures.

If you followed these steps and fixed your installation problems, give this post a share! If you ran into any issues or have a specific question about an install you are working on, be sure to leave a comment below. If I can help, I certainly will!

Thanks for watching, and be sure to like and subscribe to Darren’s Tech Tutorials for more clear, accessible tech guides! Happy coding!