Kubernetes Interview questions

How do you store sensitive data in K8 environment, will encryption guarantees 100% safety?

We use secrets to store and manage sensitive data in K8. The data will is base-64 encoded and decoded while running in clusters. But this is not completely foolproof and K8 suggests few recommendations to prevent malicious activities

1. Role based access control (RBAC) - restricts access based on roles and permissions.

2. TLS security layer

3. API authentication and authorizations

How to create a role and apply it to any service account ?

A role can be created using a yaml similar to Pods following specific template provided by kubernetes. Similarly, a Role binding yaml is created. This newly created Role and Service account are given as values in binding thus forming the connection. Once we apply the role binding yaml file, all the permissions given in role will be applied.

What are best practices to secure your deployments on K8 production environment?

Following K8 recommendations woud ensure security of our services

1. Cluster configuration using RBAC

2. Restrict access to control plane components like API, etcd

3. Namespace segregation

4. Pod security policy

What is helm and how it is useful ?

Helm is a package manager for kubernetes. Helm charts contains all resource definitions in form of yaml which are required to run a application inside a cluster. It combines everything as a single unit which makes it easier to deploy, maintain and run the application.

What are operators and how it is different from helm?

Operator and helm are both used to manage K8 applications. Helm is used for templating, managing applications.However operators extends K8 API by including the custom resources and controller to manage complex apps and their lifecycle. They automate installations, upgrades and manages failover inorder to maintain state of application.

What is AKS , how to configure and deploy a AKS cluster?

AKS is fully managed K8 service provided by Azure cloud. Inorder to deploy a cluster we need

1. Azure CLI installed and have an active subscription

2. Create a resource group

3. Create a AKS cluster

   $ az aks create \ --resource-group myResourceGroup \ --name myAKSCluster \ --node-count 3 \ --generate-ssh-keys

4. Connect to the cluster and configure 'kubectl'

What is EKS and how to deploy a EKS cluster?

EKS is AWS provided K8 service. Similar to above but few with some tweaks,

1. Additionally eksctl and kubectl need to be installed

2. Using eksctl , create a new cluster

3. Run K8 commands using kubectl

Explain few real time challenges faced in project?

Few issues faced can be related to Network policies, security document mismatches, scheduler failures, pod not deployed due to incorrect data.

What is the role of coud controller manager?

The Cloud Controller Manager (CCM) is a Kubernetes component that embeds cloud-specific control logic. It allows Kubernetes to integrate with various cloud provider services, such as load balancers, storage, and networking to K8 clusters . The CCM abstracts the cloud-specific logic from the core Kubernetes components, promoting a more modular architecture and facilitating the addition of new cloud providers.