Conquering the Beast: “Session not created: DevToolsActivePort file doesn’t exist” on Amazon Linux 2 x86 EC2 Instance

If you’re reading this, chances are you’ve encountered the frustrating error message “Session not created: DevToolsActivePort file doesn’t exist” on your Amazon Linux 2 x86 EC2 instance. Don’t worry, friend, you’re not alone! This pesky issue has plagued many a developer, but fear not, for we’ve got the solution right here.

The Culprit: Selenium WebDriver

The “Session not created: DevToolsActivePort file doesn’t exist” error is often caused by Selenium WebDriver, a popular tool for automating web browsers. When you try to run a Selenium test on your EC2 instance, the WebDriver attempts to create a new session, but fails due to the absence of the DevToolsActivePort file.

But Why, Oh Why, Does this Happen?

• EC2 instances don’t come with Chrome or Chromium pre-installed, which are required for Selenium WebDriver to function.

• Even if you install Chrome or Chromium, the DevToolsActivePort file might not be present or configured correctly.

• Selenium WebDriver versions can cause compatibility issues, leading to the error.

Solution Time!

Don’t worry, we’ve got a step-by-step guide to help you conquer this beast and get your Selenium tests running smoothly on your EC2 instance.

Step 1: Install Chrome or Chromium

First things first, you need to install Chrome or Chromium on your EC2 instance. You can choose either one, but we’ll use Chrome for this example.

sudo amazon-linux-extras install chrome

This command will install Google Chrome on your Amazon Linux 2 x86 EC2 instance.

Step 2: Configure Chrome

Next, you need to configure Chrome to allow WebDriver to connect and create a new session. Create a new file called ` chrome_options.py` with the following contents:

from selenium import webdriver
from selenium.webdriver.chrome.options import Options

options = Options()
options.add_argument("--headless")
options.add_argument("--disable-gpu")
options.add_argument("--no-sandbox")
options.add_argument("--disable-dev-shm-usage")

driver = webdriver.Chrome(options=options)

This script sets up Chrome to run in headless mode, disables GPU acceleration, and allows WebDriver to connect.

Step 3: Install Selenium WebDriver

Install the Selenium WebDriver using pip:

pip install selenium

Step 4: Create the DevToolsActivePort File

Now, create a new file called ` devtoolsactiveport.py` with the following contents:

import os

port = 9222
devtoolsactiveport_file = "/tmp/devtoolsactiveport"

if not os.path.exists(devtoolsactiveport_file):
    with open(devtoolsactiveport_file, "w") as f:
        f.write(str(port))

This script creates the DevToolsActivePort file and sets the port to 9222. You can change the port number if you need to.

Step 5: Run Your Selenium Test

Finally, run your Selenium test using the following command:

python -m selenium chrome_options.py devtoolsactiveport.py your_test_script.py

Replace `your_test_script.py` with the actual name of your Selenium test script.

Troubleshooting Tips

If you’re still encountering issues, try these troubleshooting tips:

• Check the Chrome version: Ensure you’re using a compatible Chrome version with Selenium WebDriver.

• Verify the DevToolsActivePort file: Make sure the file exists and has the correct port number.

• Check the Chrome driver version: Update the Chrome driver to the latest version using `webdriver-manager update`.

• Run the test in non-headless mode: Try running the test without the `–headless` argument to see if it works.

Conclusion

There you have it, folks! With these steps, you should be able to overcome the “Session not created: DevToolsActivePort file doesn’t exist” error on your Amazon Linux 2 x86 EC2 instance. Remember to stay calm, patient, and persistent when troubleshooting. If you’re still stuck, feel free to ask for help in the comments below.

Tip	Description
Use the latest Selenium version	Ensure you’re using the latest Selenium WebDriver version to avoid compatibility issues.
Check Chrome driver version	Verify the Chrome driver version is compatible with Selenium WebDriver.
Use a consistent environment	Maintain a consistent environment across your local machine and EC2 instance to avoid configuration issues.

Happy testing, and may the Selenium forces be with you!

Frequently Asked Question

Are you tired of dealing with the frustrating “session not created: DevToolsActivePort file doesn’t exist” error on your EC2 instance with Amazon Linux 2 x86 architecture? Don’t worry, we’ve got you covered! Check out these frequently asked questions to resolve the issue and get back to work in no time.