[Rdo-list] error ssh to overcloud nodes

Hi all, I've deployed overcloud, however I cannot login to my nodes, I get this error: [*stack@instack ~]$ openstack overcloud deploy --templates* *Deploying templates in the directory /usr/share/openstack-tripleo-heat-templates* */home/stack/.ssh/known_hosts updated.* *Original contents retained as /home/stack/.ssh/known_hosts.old* *PKI initialization in init-keystone is deprecated and will be removed.* *Warning: Permanently added '192.168.21.16' (ECDSA) to the list of known hosts.* *Permission denied (publickey,gssapi-keyex,gssapi-with-mic).* *ERROR: openstack Command '['ssh', '-oStrictHostKeyChecking=no', '-t', '-l', 'heat-admin', u'192.168.21.16', 'sudo', 'keystone-manage', 'pki_setup', '--keystone-user', "$(getent passwd | grep '^keystone' | cut -d: -f1)", '--keystone-group', "$(getent group | grep '^keystone' | cut -d: -f1)"]' returned non-zero exit status 255* Can anyone help me solve this issue? Thanks, Pedro Sousa