Introduction
The “CreateContainerConfigError” occurs during the pod creation process in Kubernetes and can lead to failed deployments. Understanding this error and knowing how to address it is crucial for maintaining a healthy and reliable Kubernetes environment.
This troubleshooting guide will explain the root causes of the “CreateContainerConfigError”, and provide practical steps to resolve it.
Common Causes of the “CreateContainerConfigError”
Here are the main causes of the error and how to fix them. Most are due to YAML configuration mistakes.
Missing ConfigMaps or Secrets
ConfigMaps and Secrets are essential for providing configuration data to your containers. If a pod references a ConfigMap or Secret that doesn’t exist, the “CreateContainerConfigError” can occur.
Incorrect Volume Mounts
If a pod specifies volume mounts that don’t match the actual volumes defined in the pod’s configuration, the error can occur.
Invalid Environment Variables
Incorrectly defined environment variables can lead to this error. Ensure that environment variables are properly set in your pod specifications.
Resource Constraints
If a container’s resource requests exceed the available resources on a node, the pod creation can fail.
Image Pull Failures
If the specified container image cannot be pulled from the registry, the pod creation will fail.
Network Issues
Network-related problems, such as DNS resolution failures or network policies, can cause the error.
Diagnosis: Identifying the “CreateContainerConfigError”
Option 1: Run kubectl get pods
Execute the following command.
kubectl get pods
Look for pods in the “CreateContainerConfigError” state.
Option 2: Inspect Pod Descriptions.
To get detailed information about a specific pod, use the following command.
kubectl describe pod <pod-name>
Look for relevant error messages, especially in the “Events” section. Common issues might include missing environment variables, volume mount errors, or image pull failures.
Option 3: Check Configurations
Verify the pod’s YAML configuration (usually defined in a Deployment or StatefulSet). Pay attention to:
- Volume mounts
- Environment variables
- Resource requests and limits
- Image specifications
- ConfigMaps and Secrets references
Option 4: Review Logs
Retrieve container logs to identify any runtime errors.
kubectl logs <pod-name> -c <container-name>
Look for clues related to configuration issues or missing resources.
Option 5: Examine Events:
Run the following command
kubectl get events
Look for events related to the affected pod. Events often provide additional context about what went wrong.
Resolution Steps for “CreateContainerConfigError”
Create Missing ConfigMaps or Secrets
If your pod references ConfigMaps or Secrets, ensure that they exist and are correctly named.
To create a ConfigMap:
kubectl create configmap my-config --from-literal=key1=value1 --from-literal=key2=value2
To create a Secret:
kubectl create secret generic my-secret --from-literal=username=myuser --from-literal=password=mypassword
br>
Verify Permissions and Resource Configurations
Check the permissions of the service account associated with your pod. Ensure it has the necessary access to ConfigMaps, Secrets, and other resources.
Also review resource requests and limits in your pod’s YAML configuration. Adjust them as needed.
Check Pod Network Connectivity
Verify that your pod can communicate with other services, databases, or external endpoints.
Test DNS resolution within the pod:
kubectl exec -it <pod-name> -- nslookup google.com
Investigate network policies or firewalls that might block communication.
