diff --git a/tripleoclient/tests/test_utils.py b/tripleoclient/tests/test_utils.py
index a00c70b6a..ed54952ff 100644
--- a/tripleoclient/tests/test_utils.py
+++ b/tripleoclient/tests/test_utils.py
@@ -190,7 +190,7 @@ class TestRunCommandAndLog(TestCase):
         self.mock_popen.assert_called_once_with(self.cmd,
                                                 stdout=subprocess.PIPE,
                                                 stderr=subprocess.STDOUT,
-                                                shell=False, bufsize=1,
+                                                shell=False,
                                                 cwd=None, env=None)
         self.assertEqual(retcode, 0)
         self.mock_logger.warning.assert_has_calls(self.log_calls,
@@ -208,7 +208,7 @@ class TestRunCommandAndLog(TestCase):
         retcode = utils.run_command_and_log(self.mock_logger, self.e_cmd)
         mock_popen.assert_called_once_with(self.e_cmd, stdout=subprocess.PIPE,
                                            stderr=subprocess.STDOUT,
-                                           shell=False, bufsize=1, cwd=None,
+                                           shell=False, cwd=None,
                                            env=None)
 
         self.assertEqual(retcode, 1)
@@ -221,7 +221,7 @@ class TestRunCommandAndLog(TestCase):
         self.mock_popen.assert_called_once_with(self.cmd,
                                                 stdout=subprocess.PIPE,
                                                 stderr=subprocess.STDOUT,
-                                                shell=False, bufsize=1,
+                                                shell=False,
                                                 cwd=None, env=test_env)
         self.assertEqual(retcode, 0)
         self.mock_logger.warning.assert_has_calls(self.log_calls,
@@ -234,7 +234,7 @@ class TestRunCommandAndLog(TestCase):
         self.mock_popen.assert_called_once_with(self.cmd,
                                                 stdout=subprocess.PIPE,
                                                 stderr=subprocess.STDOUT,
-                                                shell=False, bufsize=1,
+                                                shell=False,
                                                 cwd=test_cwd, env=None)
         self.assertEqual(retcode, 0)
         self.mock_logger.warning.assert_has_calls(self.log_calls,
@@ -246,7 +246,7 @@ class TestRunCommandAndLog(TestCase):
         self.mock_popen.assert_called_once_with(self.cmd,
                                                 stdout=subprocess.PIPE,
                                                 stderr=subprocess.STDOUT,
-                                                shell=False, bufsize=1,
+                                                shell=False,
                                                 cwd=None, env=None)
         self.assertEqual(run, self.mock_process)
         self.mock_logger.warning.assert_not_called()
diff --git a/tripleoclient/utils.py b/tripleoclient/utils.py
index 204d430a5..912e71992 100644
--- a/tripleoclient/utils.py
+++ b/tripleoclient/utils.py
@@ -1144,12 +1144,20 @@ def run_command_and_log(log, cmd, cwd=None, env=None, retcode_only=True):
     """
     proc = subprocess.Popen(cmd, stdout=subprocess.PIPE,
                             stderr=subprocess.STDOUT, shell=False,
-                            bufsize=1, cwd=cwd, env=env)
-
+                            cwd=cwd, env=env)
     if retcode_only:
-        for line in iter(proc.stdout.readline, b''):
-            # TODO(aschultz): this should probably goto a log file
-            log.warning(line.rstrip())
+        # TODO(aschultz): this should probably goto a log file
+        while True:
+            try:
+                line = proc.stdout.readline()
+            except StopIteration:
+                break
+            if line != b'':
+                if isinstance(line, bytes):
+                    line = line.decode('utf-8')
+                log.warning(line.rstrip())
+            else:
+                break
         proc.stdout.close()
         return proc.wait()
     else:
diff --git a/tripleoclient/v1/undercloud_preflight.py b/tripleoclient/v1/undercloud_preflight.py
index 351aa46fe..8905ef155 100644
--- a/tripleoclient/v1/undercloud_preflight.py
+++ b/tripleoclient/v1/undercloud_preflight.py
@@ -57,9 +57,12 @@ def _run_command(args, env=None, name=None):
     if name is None:
         name = args[0]
     try:
-        return subprocess.check_output(args,
-                                       stderr=subprocess.STDOUT,
-                                       env=env).decode('utf-8')
+        output = subprocess.check_output(args,
+                                         stderr=subprocess.STDOUT,
+                                         env=env)
+        if isinstance(output, bytes):
+            output = output.decode('utf-8')
+        return output
     except subprocess.CalledProcessError as e:
         message = '%s failed: %s' % (name, e.output)
         LOG.error(message)
@@ -155,7 +158,7 @@ def _check_hostname():
                 message = _('Configured hostname is not fully qualified.')
                 LOG.error(message)
                 raise RuntimeError(message)
-            sed_cmd = ('sed -i "s/127.0.0.1\(\s*\)/127.0.0.1\\1%s %s /" '
+            sed_cmd = (r'sed -i "s/127.0.0.1\(\s*\)/127.0.0.1\\1%s %s /" '
                        '/etc/hosts' %
                        (detected_static_hostname, short_hostname))
             args = ['sudo', '/bin/bash', '-c', sed_cmd]