Dynamodb, Failed to establish a new connection.

While running, deploy/docker-ephemeral/init.sh , in the wire-server root, I'm getting

HTTPConnectionPool(host='dynamodb', port=8000): Max retries exceeded with url: / (Caused by NewConnectionError('<botocore.awsrequest.AWSHTTPConnection object at 0x7ff6d71bcb70>: Failed to establish a new connection: [Errno -3] Temporary failure in name resolution',))

If I run deploy/docker-ephemeral/run.sh, I'm getting:

aws_cli_1 | HTTPConnectionPool(host='dynamodb', port=8000): Max retries exceeded with url: / (Caused by ConnectTimeoutError(<botocore.awsrequest.AWSHTTPConnection object at 0x7f26b8e9ce50>, 'Connection to dynamodb timed out. (connect timeout=1)'))

I've checked using:

docker-compose ps

and I got this as output:

demo_wire_dynamodb                            /docker-entrypoint.sh --sh ...   Up      127.0.0.1:4567->8000/tcp

This error is occurring for all the services i.e.:
host name: Just "elasticsearch", service name: Just "9200"): does not exist (Try again))
host name: Just "cassandra", service name: Just "9042"): does not exist (Try again)

Start by reproducing the failure with deploy/docker-ephemeral/init.sh and deploy/docker-ephemeral/run.sh, then inspect docker-compose ps and the DynamoDB, Elasticsearch, and Cassandra service names. Trace why the services cannot resolve or connect from the running containers; done means the ephemeral environment starts and all listed services are reachable without connection or name-resolution errors.