openstack npm pkgcloud createImage() function not working - openstack

Question

I am trying to create an image of an instance in openstack using npm pkgcloud.
For this I am using the code as below:
var openstack_client_compute = null;
openstack_client_compute = pkgcloud.compute.createClient({
provider: PROVIDER, // required
username: USERNAME, // required
password: PASSWORD, // required
region: REGION,
authUrl: AUTH_URL // required
});
options = {
name: 'image1', // required
server: '0e4d56a2-173a-425d-befd-cec366605522' // required
};
openstack_client_compute.createImage(options, function(err, image){
if(err){
console.log(err);
}
console.log(image);
});
I am getting the following error :
name: 'Error',
provider: 'openstack',
failCode: 'Service Unavailable',
statusCode: 503,
href: 'http://controller:8774/v2.1/6af81940df89199f088beba7d93/servers/0e4d56a2-173a-425d-befd-cec366605522/action',method: 'POST',
headers:
{ server: 'squid',
'mime-version': '1.0',
date: 'Mon, 09 Apr 2018 07:21:15 GMT',
'content-type': 'text/html;charset=utf-8',
'content-length': '3012',
'x-squid-error': 'ERR_DNS_FAIL 0',
'x-cache': 'MISS from lproxy',
'x-cache-lookup': 'MISS from proxy:8080',
connection: 'close' },
Note : other functions such as createStack deleteStack getStack etc are functioning properly
It is showing the error that unable to resolve host name (controller is not getting resolved to IP) the code is failing due to that.
Any possibility that a change in openstack configuration may resolve it.
If yes what changes are needed?