Fixing Too many open files in system Error in Apache Docker Container

If you encounter the “Too many open files in system” error in your Apache Docker container, it means that the system has reached the limit on the number of files it can open, and this is causing issues with Apache’s configuration. Here’s a step-by-step guide on how to resolve this problem.

1. Check the Current File Limit

First, you need to check the current file limit on your system to understand the magnitude of the issue. To do this, run the following command:

cat /proc/sys/fs/file-max

2. Temporarily Increase File Limit

You can temporarily increase the file limit for your Apache Docker container by executing the following command:

sysctl -w fs.file-max=500000

This command sets the maximum number of files that the system can open to 500,000. This should be enough for most use cases, but you can adjust the value if needed.

3. Verify the Changes

After executing the above command, you should verify that the changes have taken effect. You can do this by running the cat command again:

cat /proc/sys/fs/file-max

4. Make Changes Permanent

To make the changes permanent, you need to modify the sysctl configuration file. Here’s how you can do it:

vi /etc/sysctl.conf

Add the following line to the file:


Save and close the file.

5. Restart the Docker Container

Now that you have made the necessary changes, you should restart your Apache Docker container for the changes to take effect. You can do this using Docker commands, such as:

docker restart <container_name>

Replace <container_name> with the actual name or ID of your Apache Docker container.

After completing these steps, your Apache Docker container should now be running without the “Too many open files in system” error, and the file limit should remain increased even after container restarts.

Remember that setting the file limit too high may have an impact on system resources, so it’s essential to find an appropriate value that suits your specific needs. The value of 500,000 used in this guide is just an example and may not be suitable for all environments. Always monitor your system’s resource usage and adjust the file limit accordingly.