is it necessory to have same users to create passowordless login between two servers?
same users means?
what you mean to say? Will you be please a little more clear.
If user ABC want to ssh from server1 to server2 , do we need to create user ABC on server2?
No not needed…same users or different users also works, like we’ve explained in one of our SSH article at http://www.tecmint.com/ssh-passwordless-login-using-ssh-keygen-in-5-easy-steps/