Title: Running Containers with Root Account in Kubernetes (K8S)

Introduction:
In Kubernetes (K8S), containers are typically executed with non-root privileges to enhance security. However, sometimes there may be scenarios where it becomes necessary to run containers with a root account. In this article, we will discuss the process of running containers with a root account in Kubernetes and provide a step-by-step guide with code examples.

Process Overview:
The following table outlines the steps involved in running containers with root privileges in Kubernetes:

| Step | Description |
| --- | --- |
| Step 1 | Create a Docker image |
| Step 2 | Create a Kubernetes Deployment |
| Step 3 | Grant root privileges to the container |
| Step 4 | Deploy the container in Kubernetes |

Step 1: Create a Docker image
To start with, we need to create a Docker image that will act as the base image for our Kubernetes container. For the purposes of this example, let's assume we will be creating an image based on the Ubuntu operating system. Here's an example Dockerfile:

```Dockerfile
FROM ubuntu:latest
LABEL maintainer="Your Name "
USER root
```

Explanation:
- The `FROM` statement specifies the base image, which is Ubuntu in this case.
- The `LABEL` statement allows us to add metadata to the image.
- The `USER` statement switches to the root user within the container.

Step 2: Create a Kubernetes Deployment
Next, we need to create a Kubernetes Deployment file to define the container configuration. Here's an example deployment.yaml file:

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: my-app-deployment
spec:
replicas: 1
selector:
matchLabels:
app: my-app
template:
metadata:
labels:
app: my-app
spec:
containers:
- name: my-app-container
image: my-app-image:latest
securityContext:
runAsUser: 0
```

Explanation:
- The `replicas` field defines the number of desired replicas of the container.
- The `selector` field allows the deployment to select the appropriate Pods to manage.
- The `template` field specifies the configuration for creating new Pods.
- The `containers` field defines the properties of the container.
- The `securityContext` section specifies the security context for the container.
- The `runAsUser` field sets the user ID (UID) to 0, indicating root user.

Step 3: Grant root privileges to the container
In order to run the container as a root user, we need to grant the necessary privileges. This can be achieved by using a Pod Security Policy (PSP) in Kubernetes. Here's an example psp.yaml file:

```yaml
apiVersion: policy/v1beta1
kind: PodSecurityPolicy
metadata:
name: privileged
spec:
privileged: true
allowPrivilegeEscalation: true
allowedCapabilities:
- "*"
volumes:
- "*"
hostNetwork: true
hostPorts:
- min: 0
max: 65535
runAsUser:
rule: 'RunAsAny'
seLinux:
rule: 'RunAsAny'
supplementalGroups:
rule: 'RunAsAny'
fsGroup:
rule: 'RunAsAny'
```

Explanation:
- The `privileged` field allows containers to run with any privileged access on the host.
- The `allowPrivilegeEscalation` field permits processes to escalate privileges.
- The `allowedCapabilities` field grants all capabilities to the container.
- The `volumes` field allows the use of any volume type.
- The `hostNetwork` field allows the container to use the host network namespace.
- The `hostPorts` field allows the container to bind to any port on the host.
- The `runAsUser`, `seLinux`, `supplementalGroups`, and `fsGroup` fields all allow running as any user or group.

Step 4: Deploy the container in Kubernetes
Finally, we can deploy the container in Kubernetes using the created Deployment and Pod Security Policy. Apply the following command to deploy:

```bash
kubectl apply -f deployment.yaml
kubectl apply -f psp.yaml
```

Explanation:
- The `kubectl apply` command applies the configuration described in the specified YAML files to the Kubernetes cluster.

Conclusion:
Running containers with root privileges in Kubernetes can be achieved by creating a Docker image with root user access, defining a Deployment file with the necessary security context, and applying a Pod Security Policy that allows root access. By following the step-by-step process outlined in this article, now you should be able to run containers with root accounts in Kubernetes successfully. Remember to consider the security implications and use root access only when necessary. Happy containerizing!