CNCF-hosted Co-located Events Europe 2025

In containerized environments, one key challenge of pushing observability data is to identify the sender, to allow data enrichment, i.e. attaching attributes, tags, metadata based on container or Pod metadata.
This problem has been commonly solved by asking the sender to provide its own container id, easily available through /proc/self/cgroup.

When Datadog started evaluating cgroupv2, it quickly became apparent that this approach was not usable anymore, prompting us to find new solutions as the most common workaround (using mountinfo) is actually not reliable.
In this talk we'll explain why the container id is not available anymore (due private cgroup namespace) and present two solutions that we worked on.

We will go through the benefits of each one and will share how these solutions could be used in other observability projects, like OpenTelemetry.