This lightning talk explores the critical challenge of container ID resolution in cgroupv2 environments for observability data. Learn how Datadog tackled the problem when traditional methods using /proc/self/cgroup became unusable due to private cgroup namespaces. Vincent Boulineau presents two innovative solutions that maintain proper container identification for data enrichment with attributes, tags, and metadata. Discover the comparative benefits of each approach and how they can be implemented in other observability projects like OpenTelemetry. Essential viewing for anyone working with containerized environments who needs reliable container identification for proper data attribution and enrichment.