Kubernetes is an open-source plan for automating deployment, managing containerized sorts of applications, and scaling. It helps you manage your containers as well as your stateless microservices. It is a powerful tool that can be used for both development and production environments. One of its most useful features is that it allows developers to work on their local machines without worrying about ensuring their code will work on remote servers later.
This means you can build your application locally by using Docker Compose or other tools like it and then deploy it on a Kubernetes cluster without changing how you created your application locally.
Another useful feature is that Kubernetes automatically scales up or down according to the demand of each service. This means that if there’s suddenly an increase in traffic to one of your services, Kubernetes will add more instances to handle requests quickly and efficiently.
Kubernetes has made life easier.
Kubernetes has enabled the development of microservices, which were not possible before due to the complexities involved in managing containers.
Kubernetes orchestration allows developers to focus solely on their code instead of spending time managing hardware resources or scaling infrastructure. Instead, they can focus on writing code for their applications and adding new features without having to manually manage infrastructure or scale applications.
6 Kubernetes Configuration Mistakes / Errors
Despite the many benefits, there are many pitfalls to be aware of when deploying it:
- Using docker images with “latest” tags
Kubernetes is designed to work with Docker images already tagged with their version number. This means that if you use an image from the Docker Hub and do not specify a tag, then Kubernetes will assume that it should pull the latest version of the image (which may be significantly different from what you want). To avoid this problem, ensure that your docker-compose file specifies a tag or branches/tags for your containers. If you have multiple versions of an application running in production, then make sure that they are managed by Kubernetes using separate namespaces and deployments.
- Deploying containers with limited CPUs
Each node in a Kubernetes cluster has a set of CPU resources that can be allocated to running containers. In a Kubernetes pod, you can specify how many CPU cores should be allocated to your container. If you specify 0 or 1 core, then the container will not be able to use any CPU resources. You can specify the number of CPU cores using the limit Reinforcement field in PodSpec.
If you have a container that requires more CPU than available on your nodes, you may be able to increase the capacity of your cluster by adding more nodes. See Docker Machine for information about how to add more machines to your cluster.
- Failure to use Kubernetes Secrets to encode credentials such as passwords
Kubernetes Secrets are an essential tool for storing sensitive information such as passwords, API keys, and other sensitive data outside of your source code repository.
This allows you to keep your source code clean and tidy while providing access to sensitive information that is needed by applications running in your Kubernetes environment. Failure to use Kubernetes Secrets when required can result in hard-to-find bugs and security holes in your application code.
- Using a singled deployment replica
This is among the most common Kubernetes configuration mistakes/errors. When you create a deployment, you must specify the number of replicas that need to be created from this deployment. If you have specified just one replica, Kubernetes will not create more replicas even if there is capacity available on other nodes.
This can lead to incorrect load balancing and application failure if it cannot handle requests in time due to a lack of capacity on other nodes. Always specify more than one replica for your deployment to avoid this issue.
- Mapping the wrong container port to a service
This is a very common error and can be caused by many things, but the main reason is that you have not specified the right service in your Kubernetes deployment. This Wrong Kubernetes configuration could be because of an incorrect label or because you have more than one service with the same name but different labels. This can be very confusing when debugging, and many ways to fix this issue.
The first thing you should do is check if all of your services have the same label. You can do this by running kubectl to get services from your command line (or Kibana). If all of your services have the same label, you need to check if there is another service with that same name but different labels.
- Crashloopbackoff error
Crashloopbackoff is a mechanism to attempt to restart a pod that has crashed automatically. By default, Kubernetes will try to restart a pod five times with increasing delays (2s, 4s, 8s, 16s, and 32s) between retries. If none of those attempts successfully bring the pod back online, it will be marked as failed.
However, suppose you have set up an external load balancer for your cluster. In that case, it can be hard to determine whether or not your pods are truly down or just experiencing transient failures due to network issues or other transient problems outside your control. In that case, you may want to increase the number of times that Kubernetes tries to restart a crashed container before giving up on it.
Cloudify is a way to dodge quite a few pitfalls
Cloudify allows developers and DevOps teams to focus on developing their applications without the risk of making the wrong Kubernetes configuration. It supports multiple cloud providers, including AWS, Azure, Google Cloud Platform, and OpenStack, while seamlessly integrating with other cloud-native technologies like Docker and Kubernetes.
The multi-cloud Kubernetes management platform automates the provisioning of clusters by using declarative models, which are then converted into executable plans that can be executed in any cloud provider or on-premises datacenter. These plans provide a consistent workflow and ensure that tasks are executed in the right order regardless of where they run:
- Creating new clusters
- Lifecycle management (upgrades, scaling)
- Monitoring & logging
Cloudify has been designed with these Kubernetes pitfalls in mind. It can automatically handle most aspects of Kubernetes configuration for you.