I am facing getting following error while trying to resize an instance . I have 4 compute nodes, and one controller and network each. I am able to use live-migration between the compute nodes with out any issue.

I have enable following entries in the nova

allow_resize_to_same_host=true

I am getting following error in /var/log/nova/compute.log at compute node while resizing .

"/usr/lib/python2.6/site-packages/nova/virt/libvirt/driver.py", line 4907, in migrate_disk_and_power_off\n    utils.execute(\'ssh\', dest, \'mkdir\', \'-p\', inst_base)\n', '  File "/usr/lib/python2.6/site-packages/nova/utils.py", line 165, in execute\n    return processutils.execute(*cmd, **kwargs)\n', '  File "/usr/lib/python2.6/site-packages/nova/openstack/common/processutils.py", line 193, in execute\n    cmd=\' \'.join(cmd))\n', "ProcessExecutionError: Unexpected error while running command.\nCommand: ssh 10.1.15.44 mkdir -p /var/lib/nova/instances/5d5ced81-6fb1-4028-97cd-686e450d1bab\nExit code: 255\nStdout: ''\nStderr: 'Host key verification failed.\\r\\n'\n"]
    [root@compute1 ~]#

Detailed log from compute node is in

http://paste.openstack.org/show/100003/

In dashdash board I am getting following error

Error: Failed to launch instance "Test Instance 00": Please try again later [Error: Unexpected error while running command. Command: ssh 10.1.15.44 mkdir -p /var/lib/nova/instances/5d5ced81-6fb1-4028-97cd-686e450d1bab Exit code: 255 Stdout: '' Stderr: 'Host key verification failed.\r\n'].

Any idea what could be causing this. when i search i am asked to set password less authentication between nodes but I don't think that is the issue here.