Ephemeral storage in Kubernetes refers to temporary storage that is non-persistent, meaning it does not retain data once the container or pod is
terminated. This type of storage is typically used for storing temporary files that a running container can write and read. Examples of ephemeral
storage include the container’s writable layer, emptyDir volumes, and log files.
The issue arises when a container is created without any defined limits for its ephemeral storage usage. Without these limits, the container can
potentially consume all available ephemeral storage on the node where it is running.
What is the potential impact?
Resource exhaustion
Without a defined limit, a container can consume all available ephemeral storage on a node. This can lead to resource exhaustion, where no more
storage is available for other containers or processes running on the same node. This could cause these other containers or processes to fail or
perform poorly.
Unpredictable application behavior
If a container exhausts the available ephemeral storage, it can lead to unpredictable application behavior. For instance, if an application
attempts to write to the ephemeral storage and there is no space left, it may crash or exhibit other unexpected behaviors.