You mean one instance accessing another using ssh without password? Sure; set up keypairs and use user data or metadata to send the public keys up to the instances. See http://docs.openstack.org/developer/h....

i dont know much about heat templates. my target is to create a cluster with password less connection . if you have any sample template pls.

sorry - no template skills here. Use the link in my earlier comment.

Or if you don't want to learn about Heat, why don't you create your cluster manually?