When attempting to create a container within a pod, Kubernetes may encounter two types of errors: CreateContainerConfigError and CreateContainerError. These errors arise before the container reaches the running state.
To encounter these errors, you can execute the command "kubectl get pods" and view the pod status, which will display the error message shown below.
NAME READY STATUS RESTARTS AGE
pod-test-a 0/1 CreateContainerConfigError 0 0m53s
pod-test-b 0/1 CreateContainerError 0 2m05s
This article will give you some tips on how to identify and fix these errors when they are easy to solve. However, if they are more complicated, you will need to use advanced methods and tools that we won’t cover here. Keep reading until the end to learn about a tool that helps find and solve these errors quicker.
When you deploy Kubernetes, you may encounter the CreateContainerError, which indicates that the container runtime failed to create a container for your pod. This error can have different causes and resolutions depending on the situation. Next, we will discuss two common scenarios that can lead to this error and how to fix them.
In Kubernetes, a ConfigMap, is an API object that stores configuration data in a key-value format, separated from container images. It enables one or more containers within a Pod to access the configuration data, making it easier to manage an application's settings across different environments without rebuilding the container image.
In Kubernetes, Secrets are API objects used to store sensitive data, such as passwords and access keys, in an encrypted format. They enable secure access to this data by authorized containers and users within the cluster. Secrets, like ConfigMaps, separate sensitive data from container images, enabling secure and efficient deployment of applications.
To resolve the issue, locate the absent ConfigMap or Secert and either generate it within the namespace or attach another file that already exists.
NAME READY STATUS RESTARTS AGE
pod-test-a 0/1 Running 0 0m59s
It's worth noting that there is a method of controlling Kubernetes Secrets and ConfigMaps directly from within MySQL. This approach allows users to see everything in chart form, making it easy to find and replace file names. However, users may run into limitations when it comes to complex configurations or larger environments, making it necessary to revert to another tool to fully correct issues within SQL.
To diagnose and resolve a CreateContainerError, follow these steps:
Retrieve the description of the pod by running the following command and save to a text file:
kubectl describe pod [pod_name] /tmp/troubleshooting_describe_pod.txt
Search through the text file that you just created for any of the below messages in your Pod Events:
Is waiting to start
Starting container process caused
Container name [cont_name] is already in use by container
No command specified
When error is "is waiting to start", it means that an object mounted by the container could not be found or is missing.
When error is "starting container process caused",
When the error is "container name [cont_name] is already in use by container", it means that the container runtime did not delete a previous container created with a similar name.
When error is "no command specified", it means that the image configuration and pod configuration did not specify which command to run to start the container.
Please note that these steps will only resolve the most common causes of CreateContainerError. If one of these quick fixes does not work, a more complex diagnosis procedure may be necessary to identify the contributing factors in the Kubernetes environment and resolve the problem.
Kubernetes troubleshooting can be a daunting task without the right tools. Even with best practices in place, errors can still occur, leading to stressful and time-consuming investigations. That's why we developed Botkube – a tool that simplifies the process of Kubernetes troubleshooting for DevOps teams.
Botkube provides the following features to streamline the troubleshooting process:
Change Intelligence: Every error in Kubernetes is a result of a change. With Botkube, you can quickly identify who made what changes and when they made them.
Effortless Notifications: Botkube integrates seamlessly with existing communication channels like Slack, providing real-time notifications so you can quickly resolve issues as they occur.
Comprehensive Visibility: Botkube offers a complete timeline of all code and configuration changes, deployments, alerts, code diffs, pod logs, and more. All this information is presented in a single pane of glass, with simple drill-down options for further investigation.
Insight into Service Dependencies: Botkube makes it easy to visualize cross-service changes and the ripple effects of such changes across your entire system.
If you're interested in exploring Botkube and its features, sign up for a free trial using this link. With Botkube, you'll never have to waste precious time and resources looking for needles in haystacks again.