EphemeralContainers is a feature in Kubernetes that allows the creation of short-lived, disposable containers within a Pod. These ephemeral containers can be used to perform one-off tasks such as troubleshooting, debugging, or running diagnostic commands without having to modify the primary container image.
The primary use case for EphemeralContainers is for situations where additional tools or debugging utilities are required but may not be present in the main container image. Instead of modifying and rebuilding the container image, an ephemeral container can be spun up with the required tools and then destroyed once its task is complete.
Setting EphemeralContainers=true in a Pod specification enables this feature for that particular Pod. This feature is available starting from Kubernetes v1.16 and requires the kubelet version to be 1.15 or later on each node.