docs/Servers/Containerization/Kubernetes/Migrating Docker-Compose.yml to k8s.md

Migrating docker-compose.yml to Rancher RKE2 Cluster

You may be comfortable operating with Portainer or docker-compose, but there comes a point where you might want to migrate those existing workloads to a Kubernetes cluster as easily-as-possible. Lucklily, there is a way to do this using a tool called "Kompose'. Follow the instructions seen below to convert and deploy your existing docker-compose.yml into a Kubernetes cluster such as Rancher RKE2.

!!! info "RKE2 Cluster Deployment" This document assumes that you have an existing Rancher RKE2 cluster deployed. If not, you can deploy one following the [Deploy RKE2 Cluster](https://docs.bunny-lab.io/Servers/Containerization/Kubernetes/Deployment/Rancher RKE2/) documentation.

Installing Kompose

The first step involves downloading Kompose from https://kompose.io/installation. Once you have it downloaded and installed onto your environment of choice, save a copy of your docker-compose.yml file somewhere on-disk, then open up a terminal and run the following command:

kompose --file docker-compose.yaml convert --stdout > ntfy-k8s.yaml

This will attempt to convert the docker-compose.yml file into a Kubernetes manifest YAML file. The Before and after example can be seen below:

=== "(Original) docker-compose.yml"

``` yaml
version: "2.1"
services:
  ntfy:
    image: binwiederhier/ntfy
    container_name: ntfy
    command:
      - serve
    environment:
      - NTFY_ATTACHMENT_CACHE_DIR=/var/lib/ntfy/attachments
      - NTFY_BASE_URL=https://ntfy.bunny-lab.io
      - TZ=America/Denver    # optional: Change to your desired timezone
    #user: UID:GID # optional: Set custom user/group or uid/gid
    volumes:
      - /srv/containers/ntfy/cache:/var/cache/ntfy
      - /srv/containers/ntfy/etc:/etc/ntfy
    ports:
      - 80:80
    restart: always
    networks:
        docker_network:
          ipv4_address: 192.168.5.45

networks:
  default:
    external:
      name: docker_network
  docker_network:
    external: true
```

=== "(Converted) ntfy-k8s.yaml"

``` yaml
---
apiVersion: v1
kind: Service
metadata:
  annotations:
    kompose.cmd: C:\ProgramData\chocolatey\lib\kubernetes-kompose\tools\kompose.exe --file ntfy.yaml convert --stdout
    kompose.version: 1.37.0 (fb0539e64)
  labels:
    io.kompose.service: ntfy
  name: ntfy
spec:
  ports:
    - name: "80"
      port: 80
      targetPort: 80
  selector:
    io.kompose.service: ntfy

---
apiVersion: apps/v1
kind: Deployment
metadata:
  annotations:
    kompose.cmd: C:\ProgramData\chocolatey\lib\kubernetes-kompose\tools\kompose.exe --file ntfy.yaml convert --stdout
    kompose.version: 1.37.0 (fb0539e64)
  labels:
    io.kompose.service: ntfy
  name: ntfy
spec:
  replicas: 1
  selector:
    matchLabels:
      io.kompose.service: ntfy
  strategy:
    type: Recreate
  template:
    metadata:
      annotations:
        kompose.cmd: C:\ProgramData\chocolatey\lib\kubernetes-kompose\tools\kompose.exe --file ntfy.yaml convert --stdout
        kompose.version: 1.37.0 (fb0539e64)
      labels:
        io.kompose.service: ntfy
    spec:
      containers:
        - args:
            - serve
          env:
            - name: NTFY_ATTACHMENT_CACHE_DIR
              value: /var/lib/ntfy/attachments
            - name: NTFY_BASE_URL
              value: https://ntfy.bunny-lab.io
            - name: TZ
              value: America/Denver
          image: binwiederhier/ntfy
          name: ntfy
          ports:
            - containerPort: 80
              protocol: TCP
          volumeMounts:
            - mountPath: /var/cache/ntfy
              name: ntfy-claim0
            - mountPath: /etc/ntfy
              name: ntfy-claim1
      restartPolicy: Always
      volumes:
        - name: ntfy-claim0
          persistentVolumeClaim:
            claimName: ntfy-claim0
        - name: ntfy-claim1
          persistentVolumeClaim:
            claimName: ntfy-claim1

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  labels:
    io.kompose.service: ntfy-claim0
  name: ntfy-claim0
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Mi

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  labels:
    io.kompose.service: ntfy-claim1
  name: ntfy-claim1
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Mi
```