How can a pod be configured to use a ConfigMap's values?

How can a pod be configured to use a ConfigMap's values?

• A. By mounting as a volume named config
• B. By using the 'envFrom' field in the pod's yaml specification
• C. By setting imagePullPolicy
• D. By creating a PodTemplate with a ConfigMap label

Answer: (B)

ConfigMaps hold configuration as key-value pairs that containers can use. The simplest way to bring those values into a running pod as environment variables is to use envFrom in the pod’s container spec. By referencing the ConfigMap with a configMapRef, every key in the ConfigMap becomes an environment variable inside the container with the same name and its corresponding value. This lets the application read its configuration directly from environment variables, which is a common pattern in Kubernetes. Mounting the ConfigMap as a volume is another valid method, which would expose the keys as files inside the container’s filesystem, but it doesn’t populate environment variables. The other option mentioned (imagePullPolicy) is unrelated to consuming ConfigMap data, and a PodTemplate with a ConfigMap label doesn’t automatically inject the ConfigMap’s values.

ConfigMaps hold configuration as key-value pairs that containers can use. The simplest way to bring those values into a running pod as environment variables is to use envFrom in the pod’s container spec. By referencing the ConfigMap with a configMapRef, every key in the ConfigMap becomes an environment variable inside the container with the same name and its corresponding value. This lets the application read its configuration directly from environment variables, which is a common pattern in Kubernetes.

Mounting the ConfigMap as a volume is another valid method, which would expose the keys as files inside the container’s filesystem, but it doesn’t populate environment variables. The other option mentioned (imagePullPolicy) is unrelated to consuming ConfigMap data, and a PodTemplate with a ConfigMap label doesn’t automatically inject the ConfigMap’s values.