Debug Your Application

When deploying your application on the Phala Cloud UI, you can choose between two types of CVM base images: dstack-<version> and dstack-dev-<version>. The dev image allows you to log in to the CVM in the future for debugging purposes. If you opt for a non-dev image, rest assured that no one will have the ability to access your CVM, either physically or remotely.

[!ALERT] The dev image is not recommended for production environments.

For example, to enable the use of tool ttypd for logging into your CVM from a web browser, you need to add a ttypd service to your Docker Compose file as shown below:

services:
  alpine-ttypd:
    build: .
    image: hackinglab/alpine-ttyd-bash:3.2
    environment:
    - AUTHOR=e1
    - HL_USER_USERNAME=root
    - HL_USER_PASSWORD=123QWEasd
    ports:
      - 7681:7681
    volumes:
      - /:/host
    network_mode: host

You can then view a specific endpoint for the ttypd service by navigating to "View Details" → "Network." and if you check the Container tab, you will see there is a container running for the ttypd service.

When you open this endpoint in your browser (in this case, https://7c7629f605a50abe5797e1b6bab115fec6b9e7ac-7681.dstack-prod5.phala.network/), you will see a terminal interface. The next step is to install the openssh-client.

[!NOTE] The base image is not Debian-based, so you will not be able to use the apt package manager. Instead, you will use the apk package manager.

You can now log in to the CVM using the command ssh root@localhost. As shown below, you can retrieve information about running Docker containers by executing the command docker ps -a within the CVM.