[Question]: Is the entrypoint of a Dockerfile respected when being used as the base of a container job?

[james-ro-williams]

Task name

Task version

Environment type (Please select at least one enviroment where you face this issue)

• Self-Hosted
• Microsoft Hosted
• VMSS Pool
• Container

Azure DevOps Server type

dev.azure.com (formerly visualstudio.com)

Azure DevOps Server Version (if applicable)

No response

Operation system

Ubuntu 24.04 (Noble)

Question

Hi,

We are using a custom Docker image built from the C++ Ubuntu Noble dev container image hosted here: https://mcr.microsoft.com/en-us/artifact/mar/devcontainers/cpp/ as the base for a custom task running as a container job in Azure Pipelines.

In the ENTRYPOINT of the Docker image, we do some setup which results in the setting of some environment variables for all users inside any container running the Docker image. When building and running locally, this works and the environment variables are set as expected. However, when using this image in a container job, we see no evidence of the ENTRYPOINT being evaluated at all.

So my question is this: is the ENTRYPOINT of a Docker image overridden when using it as the basis for a container job?