Telepresence in Docker Mode

2. Try the Emojivoto application

The remote cluster is running the Emojivoto application, which consists of four services. Test out the application:

1. Go to the remote demo cluster and vote for some emojis.

   If the link to the remote demo cluster doesn't work, make sure you don't have an ad blocker preventing it from opening.

2. Now, click on the 🍩 emoji. You'll see that a bug is present, and voting 🍩 doesn't work. We're going to use Telepresence shortly to fix this bug, as everyone should be able to vote for 🍩!

3. Testing the fix in your local environment

We'll set up a development environment locally on your workstation. We'll then use Telepresence to connect this local development environment to the remote Kubernetes cluster. To save time, the development environment we'll use is pre-packaged as a Docker container.

1. Download and run the image for the service locally:

   If you're using Docker Desktop on Windows, you may need to enable virtualization to run the container.
   > Make sure that ports 8080 and 8083 are free. If the Docker engine is not running, the command will fail and you will see docker: unknown server OS in your terminal.

   The Docker container includes a copy of the Emojivoto application that fixes the bug. Visit the leaderboard and notice how it is different from the leaderboard in your Kubernetes cluster.

2. Now, stop the container by running the following command in your terminal:

In this section of the quickstart, you ran the Emojivoto application locally. In the next section, you'll use Telepresence to connect your local development environment to the remote Kubernetes cluster.

4. Download the demo cluster config file

1. Download your demo cluster config file. This file contains the credentials you need to access your demo cluster.

2. Export the file's location to KUBECONFIG by running this command in your terminal:

   GNU/Linux

   macOS

   Windows

You should now be able to run kubectl commands against your demo cluster.

3. Verify that you can access the cluster by listing the app's services:

5. Enable Telepresence Docker mode

You can simply add the docker flag to any Telepresence command, and it will start your daemon in a container. Thus removing the need for root access, making it easier to adopt as an organization.

1. Confirm that the Telepresence CLI is now installed, we expect to see that the daemons are not yet running: telepresence status

   macOS users: If you receive an error when running Telepresence that the developer cannot be verified, open System Preferences → Security & Privacy → General. Click Open Anyway at the bottom to bypass the security block. Then retry the telepresence status command.

2. Log in to Ambassador Cloud:

3. Then, install the Helm chart and quit Telepresence:

4. Finally, connect to the remote cluster using Docker mode:

5. Verify that you are connected to the remote cluster by listing your Docker containers:

This method limits the scope of the potential networking issues since everything stays inside Docker. The Telepresence daemon can be found under the name tp-<your-context> when listing your containers.

6. Set up your local development environment and make a global intercept

Start your intercept handler (interceptor) by targeting the daemon container --network=container:tp-<your-context>, and open the preview URL to see the traffic routed to your machine.

1. Run the Docker container locally, by running this command inside your local terminal. The image is the same as the one you ran in the previous step (step 1) but this time, you will run it with the --network=container:tp-<your-context> flag:

2. With Telepresence, you can create global intercepts that intercept all traffic going to a service in your cluster and route it to your local environment instead/ Start a global intercept by running this command in your terminal:

   Learn more about intercepts and how to use them.

7. Make a personal intercept

Personal intercepts allow you to be selective and intercept only some of the traffic to a service while not interfering with the rest of the traffic. This allows you to share a cluster with others on your team without interfering with their work.

1. First, connect to telepresence docker mode again:

2. Run the docker container again:

3. Create a personal intercept by running this command in your terminal:

4. Open the preview URL to see the traffic routed to your machine.

5. To stop the intercept, run this command in your terminal:

What's Next?

You've intercepted a service in one of our demo clusters, now you can use Telepresence to intercept a service in your own environment!