Configure CTM on a Subdomain Using AWS CloudFront

Emily Dye

March 17, 2026 18:22

CloudFront allows you to load the tracking code through your domain, accelerating delivery and enabling whitelabel support. Follow these steps to run CTM functionality through a subdomain.

Step 1: Create a CloudFront Distribution

Log in to the AWS Console.
In the search bar, type CloudFront and select it.
In the left-hand menu, click Distributions.
Click Create Distribution in the top-right corner.
Leave all settings at their defaults unless specified below.
Select your package. You can start with the Free package.
Enter a name for your distribution.
Set Distribution Type to Single website or app.

Configure Origin

Set Origin Type to Other.
In Custom Origin, enter:

cdn.tctm.co

Add Required Headers

Under Settings, click Customize Origin Settings.
Click Add Header and add the following:

Header Name: x-cdn
Value: cloudfront
Header Name: x-act
Value: your CTM Account ID

Ensure there are no extra spaces when copying and pasting.

Configure Cache Settings

Select Customize Cache Settings.
Set Allowed HTTP Methods to:

GET, HEAD, OPTIONS, PUT, POST, PATCH, DELETE

Set the following policies:

Cache Policy: CachingDisabled
Origin Request Policy: AllViewer

Continue to the next page.
Do not enable security. If the option is unavailable, leave the settings at their default.
Click Create Distribution.

Step 2: Create a Second Behavior

Open your distribution.
Click the Behaviors tab.
Click Create Behavior.

Configure Behavior

Set Path Pattern to:
```
/*.js
```
Select your origin from the dropdown.

Set Allowed HTTP Methods to:

GET, HEAD, OPTIONS, PUT, POST, PATCH, DELETE

Select Customize Cache Settings and apply:
- Cache Policy: CachingDisabled
- Origin Request Policy: AllViewer
Click Create Behavior.

Step 3: Request an SSL Certificate

In the AWS Console, search for Certificate Manager and open it.
Click Request.
Select Request a public certificate and click Next.
Select N. Virginia as the Region in the top-right dropdown.

Add Domain

Enter your subdomain:
```
ctm.yourdomain.com
```
Example:
```
ctm.testing.com
```
Leave other settings as the default.
Click Request.

Step 4: Add DNS Records for Certificate Validation

Open the certificate you just created.
Locate the CNAME Name and CNAME Value.
Add these records in your DNS provider.
Return to Certificate Manager and wait for the status to change from Pending to Issued.
Refresh the page to check the status.
This process can take 5 to 60 minutes.

Important Notes

Some DNS providers automatically append your domain.
If your provider does this, remove the domain portion from the CNAME Name before entering it.
If your provider requires the full value, enter it exactly as shown.
Paste the CNAME Value exactly as provided.

Step 5: Final CloudFront Configuration

Go back to your CloudFront distribution.
Under the General tab, click Edit.

Update Settings

In Alternate Domain Name (CNAME), enter:
```
ctm.yourdomain.com
```
In Custom SSL Certificate, select the certificate you created.
Click Save Changes.

Step 6: Add Subdomain to DNS

In your CloudFront distribution, locate the Distribution Domain Name.
Example:
```
d123example.cloudfront.net
```
Copy this value.

Create DNS Record

Go to your DNS provider.
Add a new CNAME record:
- Name: ctm
- Value: your CloudFront distribution domain
Save the record.

Step 7: Allow for Propagation

Changes may take up to one hour to propagate.
If you see a "Not Secured" message in your browser, propagation is still in progress.

Step 8: Run Validation Tests

Open the following URLs in your browser:

```
https://ctm.yourdomain.com/t.js
```
Expected result: JavaScript code is displayed.
```
https://ctm.yourdomain.com/x.json
```
Expected result: No errors.

Step 9: Update Your Tracking Code

Once validation is successful, update your website tracking script:

<script src="https://ctm.yourdomain.com/t.js"></script>