Comment 7 for bug 1717302

Even with the above patches (bad arping arguments, arping error), we still have a failure:

http://logs.openstack.org/84/500384/18/check/gate-tempest-dsvm-neutron-dvr-multinode-scenario-ubuntu-xenial-nv/a427ec7/logs/testr_results.html.gz

Traceback (most recent call last):
  File "/opt/stack/new/neutron/neutron/tests/tempest/scenario/test_floatingip.py", line 139, in test_east_west
    self._test_east_west()
  File "/opt/stack/new/neutron/neutron/tests/tempest/scenario/test_floatingip.py", line 119, in _test_east_west
    dest_server['port']['fixed_ips'][0]['ip_address'])
  File "/opt/stack/new/neutron/neutron/tests/tempest/scenario/base.py", line 279, in check_remote_connectivity
    source, dest, should_succeed, nic, mtu, fragmentation))
  File "/opt/stack/new/neutron/neutron/tests/tempest/scenario/base.py", line 274, in _check_remote_connectivity
    1)
  File "tempest/lib/common/utils/test_utils.py", line 103, in call_until_true
    if func():
  File "/opt/stack/new/neutron/neutron/tests/tempest/scenario/base.py", line 259, in ping_remote
    fragmentation=fragmentation)
  File "/opt/stack/new/neutron/neutron/tests/tempest/scenario/base.py", line 254, in ping_host
    return source.exec_command(cmd)
  File "tempest/lib/common/ssh.py", line 151, in exec_command
    ssh = self._get_ssh_connection()
  File "tempest/lib/common/ssh.py", line 121, in _get_ssh_connection
    password=self.password)
tempest.lib.exceptions.SSHTimeout: Connection to the 172.24.5.6 via SSH timed out.
User: ubuntu, Password: None

Still need to track this down.