How to set up Server-side Tagging with Google Tag Manager

Setting up server-side tagging with Google Tag Manager (GTM) involves configuring a server-side container, setting up a tagging server, and ensuring that your web properties send data to this server. Server-side tagging helps improve data security, enhance website performance, and ensure data accuracy. Here’s a step-by-step tutorial on how to set up server-side tagging with Google Tag Manager.

 1. Create a Server-Side Container

1. Log in to GTM:

   • Go to Google Tag Manager.

2. Create a New Container:

   • Click on the three dots next to your account name.
   • Select Admin and then click + Create Container.
   • Choose Server as the container type and name your container.
   • Click Create.

 2. Set Up the Tagging Server

You can use Google Cloud Platform (GCP), AWS, or any other cloud service to host your tagging server. For simplicity, this guide uses GCP.

2.1 Set Up Google Cloud Project

1. Create a New Project:

   • Go to Google Cloud Console.
   • Click on the project dropdown and select New Project.
   • Enter a project name and click Create.

2. Enable APIs:

   • In the new project, go to APIs & Services > Library.
   • Enable the App Engine API and the Identity and Access Management (IAM) API.

2.2 Deploy Tagging Server

1. Deploy the GTM Server Container:

   • Go back to your GTM server container setup screen.
   • Click Get Started under "Automatic Provisioning".
   • Follow the instructions to deploy the server on Google Cloud.
   • This will create an App Engine instance running the tagging server.

2. Set Up the DNS and SSL:

   • Configure your custom domain and SSL certificate through Google Cloud.
   • Follow instructions in the GTM interface for setting up DNS records.

 3. Configure Client-Side GTM to Send Data to Server-Side GTM

3.1 Update Web Container Settings

1. Modify Existing Tags:

   • Go to your web GTM container.
   • Open each tag you want to route through the server.
   • In the tag configuration, set the endpoint to your server-side GTM URL.
   • For example, change the Google Analytics endpoint to https://<your-gtm-server-domain>/collect.

2. Create a New Tag for Server-Side Forwarding:

   • If you don’t want to modify existing tags, create a new tag to forward data to the server.
   • Set up a custom HTML tag or use a tag template for forwarding data to the server-side container.

3.2 Update Analytics Tags

1. Google Analytics 4:

   • In your GA4 tag settings, change the Measurement Protocol API Secret to the endpoint provided by your server-side container.
   • Use the GTM Server URL in your tag configuration.

2. Universal Analytics:

   • For Universal Analytics, change the tracking endpoint to the server-side GTM URL.
   • This can be done by modifying the tag's settings or using a custom HTML tag to send the data.

 4. Configure Server-Side GTM Container

4.1 Set Up Clients

1. Create New Clients:

   • In your server-side GTM container, go to the Clients section.
   • Create new clients to handle incoming data from various sources (e.g., Google Analytics, Facebook).

2. Configure Clients:

   • Configure each client with the appropriate settings to parse and handle the incoming data.
   • For example, set up a GA4 client to handle GA4 events.

4.2 Create Server-Side Tags

1. Create New Tags:

   • In the server-side GTM container, go to the Tags section.
   • Create new tags to process and forward the data as needed.

2. Configure Tag Settings:

   • Configure the tags to send data to the appropriate endpoints.
   • For example, set up a GA4 tag to send data to Google Analytics.

 5. Test and Publish

5.1 Testing

1. Preview Mode:

   • Use GTM’s preview mode to test your setup.
   • Verify that data is sent from the client-side container to the server-side container and then forwarded to the appropriate services.

2. Check Server Logs:

   • Review logs in your Google Cloud Console to ensure data is processed correctly by the tagging server.

3. Validate Data in Analytics:

   • Check Google Analytics or other services to ensure the data is being recorded accurately.

5.2 Publish

1. Publish Server-Side Container:

   • Once testing is complete, publish your server-side container.

2. Publish Client-Side Changes:

   • Publish changes to your client-side GTM container to complete the setup.

Additional Tips and Best Practices

1. Security

• Secure Endpoints:

  • Ensure all endpoints are secure and use HTTPS.
  • Implement IP whitelisting if needed.

• Authentication:

  • Use authentication tokens to verify incoming data requests.

2. Monitoring

• Set Up Alerts:
  • Configure alerts in Google Cloud to monitor the health and performance of your tagging server.
  • Use logging and monitoring tools to keep track of data flow and potential issues.

3. Optimize Performance

• Caching:

  • Implement caching mechanisms to reduce load on your server.
  • Use Cloud CDN to cache static resources.

• Minimize Payloads:

  • Optimize the data payloads to minimize the amount of data sent.

4. Compliance

• Privacy Regulations:
  • Ensure your setup complies with data privacy regulations like GDPR and CCPA.
  • Implement user consent mechanisms where required.

By following these steps, you can set up a robust server-side tagging infrastructure with Google Tag Manager. This setup not only improves data accuracy and security but also enhances website performance by offloading tracking tasks to a dedicated server. Regularly review and optimize your setup to maintain its efficiency and effectiveness.