Docker – Kamal (Ruby on Rails) is not able to resolve environmental variables or paths

My rails application has the following

• Dockerfile
• config/deploy.yml
• .env

I am trying to do

kamal env push
INFO [55b3675b] Running /usr/bin/env mkdir -p .kamal on ${SERVER_IP}
ERROR (Socket::ResolutionError): Exception while executing on host ${SERVER_IP}: getaddrinfo: No such host is known.

Whatever I do, I am not able to get kamal resolve my variables from .env file, it works if I hard code all the variables into the deploy.yml itself

What am I doing wrong? I have no clue how to debug as well.

In fact even when I am trying to give path for my private key which is in my ~.sshid_rsa, it is not able to find it! I had to put the private key itself in my deploy.yml to make it work.

( I am using git bash in windows)

My deploy.yml looks like this

# Name of your application. Used to uniquely configure containers.
service: myapp

# Name of the container image.
image: ${DOCKER_USERNAME}/myapp

# Deploy to these servers.
servers:
  web:
    - ${SERVER_IP}

# Credentials for your image host.
registry:
  username: 
    - ${DOCKER_USERNAME}
  password: 
    - ${DOCKER_PASSWORD}

# Inject ENV variables into containers.
env:
  clear:
    REDIS_URL: ${REDIS_URL}
    DOMAIN: ${DOMAIN}
  secret:
    - RAILS_MASTER_KEY
    - LETSENCRYPT_EMAIL

# Use accessory services.
accessories:
  redis:
    image: redis:7-alpine
    host: ${SERVER_IP}
    port: 6379

# Configure custom arguments for Traefik.
traefik:
  args:
    entryPoints.web.address: ":80"
    entryPoints.websecure.address: ":443"
    certificatesResolvers.letsencrypt.acme.email: ${LETSENCRYPT_EMAIL}
    certificatesResolvers.letsencrypt.acme.storage: "/letsencrypt/acme.json"
    certificatesResolvers.letsencrypt.acme.httpChallenge.entryPoint: "web"
  options:
    publish:
      - "443:443"
    volume:
      - "/letsencrypt:/letsencrypt"

# Configure a custom healthcheck
healthcheck:
  path: /up
  port: 3000

asset_path: /rails/public

boot:
  limit: 25%
  wait: 5

ssh:
  user: root
  keys: 
    - ${SSH_PRIVATE_KEY_PATH}