diff --git a/.travis.yml b/.travis.yml
index 216df98..32c22f2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -21,6 +21,7 @@ install:
 script:
   - pylama
   - wget --quiet netng.pl/routeros_test_images/routeros_6.33.3.qcow2 -O images/routeros_6.33.3.qcow2
+  - wget --quiet netng.pl/routeros_test_images/routeros_6.43rc21.qcow2 -O images/routeros_6.43rc21.qcow2
   - py.test --pylama
 deploy:
   provider: pypi
diff --git a/images/README.md b/images/README.md
index ce698e2..bc57634 100644
--- a/images/README.md
+++ b/images/README.md
@@ -15,5 +15,6 @@ qemu-system-i386 \
     -cdrom ISO_FILE.iso \
     -vnc :3
 ```
-Install every package except:
-- kvm
+
+*   Install every package except `kvm`
+*   Add `dhcp-client` on `ether1`
diff --git a/librouteros/__init__.py b/librouteros/__init__.py
index 5e25564..feeadee 100644
--- a/librouteros/__init__.py
+++ b/librouteros/__init__.py
@@ -43,13 +43,19 @@ def connect(host, username, password, **kwargs):
     api = arguments['subclass'](protocol=protocol)
 
     try:
-        sentence = api('/login')
+        # First send dummy credentials to know if we get a =ret= back.
+        # This way we know if it is a pre 6.43 auth method or not.
+        sentence = api('/login', **{'name': 'dummy_user', 'password': 'dummy_password'})
         token = sentence[0]['ret']
-        encoded = encode_password(token, password)
-        api('/login', **{'name': username, 'response': encoded})
-    except (ConnectionError, TrapError, FatalError, MultiTrapError):
+    except (TrapError, MultiTrapError):
+        # Login failed so use 6.43 auth method.
+        api('/login', **{'name': username, 'password': password})
+    except (ConnectionError, FatalError):
         transport.close()
         raise
+    else:
+        # We got =ret= so use pre 6.43 auth method.
+        api('/login', **{'name': username, 'response': encode_password(token, password)})
 
     return api
 
diff --git a/tests/integration/conftest.py b/tests/integration/conftest.py
index e1134c0..1c79f54 100644
--- a/tests/integration/conftest.py
+++ b/tests/integration/conftest.py
@@ -23,7 +23,7 @@ def api_session():
         raise librouteros.ConnectionError('could not connect to device')
 
 
-@pytest.fixture(scope='session')
+@pytest.fixture(scope='session', params=('6.33.3', '6.43rc21'))
 def disk_image(request):
     """Create a temporary disk image backed by original one."""
     img = NamedTemporaryFile()
@@ -32,7 +32,7 @@ def disk_image(request):
         'qemu-img', 'create',
         '-f', 'qcow2',
         # Path to backing file must be absolute or relative to new image
-        '-b', str(py.path.local().join('images/routeros_6.33.3.qcow2')),
+        '-b', str(py.path.local().join('images/routeros_{}.qcow2'.format(request.param))),
         img.name,
     ]
     check_call(cmd, stdout=DEV_NULL)