Update of latest tests.

Change-Id: Ifb04651ff4a3c1ba9aaa725eb9a309278ebc1140
Signed-off-by: Stefan Kobza <skobza@cisco.com>

8 files changed, 502 insertions, 35 deletions

diff --git a/resources/libraries/python/CrossConnectSetup.py b/resources/libraries/python/CrossConnectSetup.py
new file mode 100644
index 0000000000..3f1f7d42b6
--- /dev/null
+++ b/resources/libraries/python/CrossConnectSetup.py
@@ -0,0 +1,45 @@
+# Copyright (c) 2016 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Library to set up cross-connect in topology."""
+
+from resources.libraries.python.VatExecutor import VatExecutor
+from resources.libraries.python.topology import Topology
+
+__all__ = ['CrossConnectSetup']
+
+class CrossConnectSetup(object):
+    """Crossconnect setup in topology."""
+
+    def __init__(self):
+        pass
+
+    @staticmethod
+    def vpp_setup_bidirectional_cross_connect(node, interface1, interface2):
+        """Create crossconnect between 2 interfaces on vpp node.
+
+        :param node: Node to add bidirectional crossconnect
+        :param interface1: first interface
+        :param interface2: second interface
+        :type node: dict
+        :type interface1: str
+        :type interface2: str
+        """
+        sw_iface1 = Topology().get_interface_sw_index(node, interface1)
+        sw_iface2 = Topology().get_interface_sw_index(node, interface2)
+        VatExecutor.cmd_from_template(node, "l2_xconnect.vat",
+                                      interface1=sw_iface1,
+                                      interface2=sw_iface2)
+        VatExecutor.cmd_from_template(node, "l2_xconnect.vat",
+                                      interface1=sw_iface2,
+                                      interface2=sw_iface1)
diff --git a/resources/libraries/python/IPv4NodeAddress.py b/resources/libraries/python/IPv4NodeAddress.py
index 0f2c1d9cd3..8db9ffafe3 100644
--- a/resources/libraries/python/IPv4NodeAddress.py
+++ b/resources/libraries/python/IPv4NodeAddress.py
@@ -19,9 +19,9 @@
 from ipaddress import IPv4Network
 
 # Default list of IPv4 subnets
-IPV4_NETWORKS = ['192.168.1.0/24',
-                 '192.168.2.0/24',
-                 '192.168.3.0/24']
+IPV4_NETWORKS = ['20.20.20.0/24',
+                 '10.10.10.0/24',
+                 '1.1.1.0/30']
 
 
 class IPv4NetworkGenerator(object):
diff --git a/resources/libraries/python/IPv4Util.py b/resources/libraries/python/IPv4Util.py
index 5480bfcea3..d3a016d767 100644
--- a/resources/libraries/python/IPv4Util.py
+++ b/resources/libraries/python/IPv4Util.py
@@ -45,6 +45,7 @@ class IPv4Node(object):
     @abstractmethod
     def set_ip(self, interface, address, prefix_length):
         """Configure IPv4 address on interface
+
         :param interface: interface name
         :param address:
         :param prefix_length:
@@ -58,6 +59,7 @@ class IPv4Node(object):
     @abstractmethod
     def set_interface_state(self, interface, state):
         """Set interface state
+
         :param interface: interface name string
         :param state: one of following values: "up" or "down"
         :return: nothing
@@ -67,6 +69,7 @@ class IPv4Node(object):
     @abstractmethod
     def set_route(self, network, prefix_length, gateway, interface):
         """Configure IPv4 route
+
         :param network: network IPv4 address
         :param prefix_length: mask length
         :param gateway: IPv4 address of the gateway
@@ -82,6 +85,7 @@ class IPv4Node(object):
     @abstractmethod
     def unset_route(self, network, prefix_length, gateway, interface):
         """Remove specified IPv4 route
+
         :param network: network IPv4 address
         :param prefix_length: mask length
         :param gateway: IPv4 address of the gateway
@@ -97,6 +101,7 @@ class IPv4Node(object):
     @abstractmethod
     def flush_ip_addresses(self, interface):
         """Flush all IPv4 addresses from specified interface
+
         :param interface: interface name
         :type interface: str
         :return: nothing
@@ -106,6 +111,7 @@ class IPv4Node(object):
     @abstractmethod
     def ping(self, destination_address, source_interface):
         """Send an ICMP request to destination node
+
         :param destination_address: address to send the ICMP request
         :param source_interface:
         :type destination_address: str
@@ -167,6 +173,7 @@ class Dut(IPv4Node):
 
     def get_sw_if_index(self, interface):
         """Get sw_if_index of specified interface from current node
+
         :param interface: interface name
         :type interface: str
         :return: sw_if_index of 'int' type
@@ -175,6 +182,7 @@ class Dut(IPv4Node):
 
     def exec_vat(self, script, **args):
         """Wrapper for VAT executor.
+
         :param script: script to execute
         :param args: parameters to the script
         :type script: str
@@ -184,6 +192,20 @@ class Dut(IPv4Node):
         # TODO: check return value
         VatExecutor.cmd_from_template(self.node_info, script, **args)
 
+    def set_arp(self, interface, ip_address, mac_address):
+        """Set entry in ARP cache.
+
+        :param interface: Interface name.
+        :param ip_address: IP address.
+        :param mac_address: MAC address.
+        :type interface: str
+        :type ip_address: str
+        :type mac_address: str
+        """
+        self.exec_vat('add_ip_neighbor.vat',
+                      sw_if_index=self.get_sw_if_index(interface),
+                      ip_address=ip_address, mac_address=mac_address)
+
     def set_ip(self, interface, address, prefix_length):
         self.exec_vat('add_ip_address.vat',
                       sw_if_index=self.get_sw_if_index(interface),
@@ -224,6 +246,7 @@ class Dut(IPv4Node):
 
 def get_node(node_info):
     """Creates a class instance derived from Node based on type.
+
     :param node_info: dictionary containing information on nodes in topology
     :return: Class instance that is derived from Node
     """
@@ -238,6 +261,7 @@ def get_node(node_info):
 
 def get_node_hostname(node_info):
     """Get string identifying specifed node.
+
     :param node_info: Node in the topology.
     :type node_info: Dict
     :return: String identifying node.
@@ -264,8 +288,32 @@ class IPv4Util(object):
     topology_helper = None
 
     @staticmethod
+    def setup_arp_on_all_duts(nodes_info):
+        """For all DUT nodes extract MAC and IP addresses of adjacent interfaces
+        from topology and use them to setup ARP entries.
+
+        :param nodes_info: Dictionary containing information on all nodes
+        in topology.
+        :type nodes_info: dict
+        """
+        for node in nodes_info.values():
+            if node['type'] == NodeType.TG:
+                continue
+            for interface, interface_data in node['interfaces'].iteritems():
+                if interface == 'mgmt':
+                    continue
+                interface_name = interface_data['name']
+                adj_node, adj_int = Topology.\
+                    get_adjacent_node_and_interface(nodes_info, node,
+                                                    interface_name)
+                ip_address = IPv4Util.get_ip_addr(adj_node, adj_int['name'])
+                mac_address = adj_int['mac_address']
+                get_node(node).set_arp(interface_name, ip_address, mac_address)
+
+    @staticmethod
     def next_address(subnet):
         """Get next unused IPv4 address from a subnet
+
         :param subnet: holds available IPv4 addresses
         :return: tuple (ipv4_address, prefix_length)
         """
@@ -281,6 +329,7 @@ class IPv4Util(object):
     @staticmethod
     def next_network(nodes_addr):
         """Get next unused network from dictionary
+
         :param nodes_addr: dictionary of available networks
         :return: dictionary describing an IPv4 subnet with addresses
         """
@@ -290,7 +339,9 @@ class IPv4Util(object):
 
     @staticmethod
     def configure_ipv4_addr_on_node(node, nodes_addr):
-        """Configure IPv4 address for all interfaces on a node in topology
+        """Configure IPv4 address for all non-management interfaces
+        on a node in topology.
+
         :param node: dictionary containing information about node
         :param nodes_addr: dictionary containing IPv4 addresses
         :return:
@@ -305,16 +356,20 @@ class IPv4Util(object):
             network = IPv4Util.topology_helper[interface_data['link']]
             address, prefix = IPv4Util.next_address(network)
 
-            get_node(node).set_ip(interface_data['name'], address, prefix)
+            if node['type'] != NodeType.TG:
+                get_node(node).set_ip(interface_data['name'], address, prefix)
+                get_node(node).set_interface_state(interface_data['name'], 'up')
+
             key = (get_node_hostname(node), interface_data['name'])
             IPv4Util.ADDRESSES[key] = address
             IPv4Util.PREFIXES[key] = prefix
             IPv4Util.SUBNETS[key] = network['subnet']
 
     @staticmethod
-    def nodes_setup_ipv4_addresses(nodes_info, nodes_addr):
+    def dut_nodes_setup_ipv4_addresses(nodes_info, nodes_addr):
         """Configure IPv4 addresses on all non-management interfaces for each
-        node in nodes_info
+        node in nodes_info if node type is not traffic generator
+
         :param nodes_info: dictionary containing information on all nodes
         in topology
         :param nodes_addr: dictionary containing IPv4 addresses
@@ -323,16 +378,17 @@ class IPv4Util(object):
         IPv4Util.topology_helper = {}
         # make a deep copy of nodes_addr because of modifications
         nodes_addr_copy = copy.deepcopy(nodes_addr)
-        for _, node in nodes_info.iteritems():
+        for node in nodes_info.values():
             IPv4Util.configure_ipv4_addr_on_node(node, nodes_addr_copy)
 
     @staticmethod
     def nodes_clear_ipv4_addresses(nodes):
         """Clear all addresses from all nodes in topology
+
         :param nodes: dictionary containing information on all nodes
         :return: nothing
         """
-        for _, node in nodes.iteritems():
+        for node in nodes.values():
             for interface, interface_data in node['interfaces'].iteritems():
                 if interface == 'mgmt':
                     continue
@@ -343,6 +399,7 @@ class IPv4Util(object):
     @keyword('Node "${node}" interface "${interface}" is in "${state}" state')
     def set_interface_state(node, interface, state):
         """See IPv4Node.set_interface_state for more information.
+
         :param node:
         :param interface:
         :param state:
@@ -357,6 +414,7 @@ class IPv4Util(object):
              '"${address}" with prefix length "${prefix_length}"')
     def set_interface_address(node, interface, address, length):
         """See IPv4Node.set_ip for more information.
+
         :param node:
         :param interface:
         :param address:
@@ -387,6 +445,7 @@ class IPv4Util(object):
              '"${gateway}"')
     def set_route(node, network, prefix_length, interface, gateway):
         """See IPv4Node.set_route for more information.
+
         :param node:
         :param network:
         :param prefix_length:
@@ -407,6 +466,7 @@ class IPv4Util(object):
              '"${gateway}"')
     def unset_route(node, network, prefix_length, interface, gateway):
         """See IPv4Node.unset_route for more information.
+
         :param node:
         :param network:
         :param prefix_length:
@@ -417,12 +477,15 @@ class IPv4Util(object):
         get_node(node).unset_route(network, prefix_length, gateway, interface)
 
     @staticmethod
-    @keyword('After ping is sent from node "${src_node}" interface '
-             '"${src_port}" with destination IPv4 address of node '
-             '"${dst_node}" interface "${dst_port}" a ping response arrives '
-             'and TTL is decreased by "${ttl_dec}"')
-    def send_ping(src_node, src_port, dst_node, dst_port, hops):
+    @keyword('After ping is sent in topology "${nodes_info}" from node '
+             '"${src_node}" interface "${src_port}" with destination IPv4 '
+             'address of node "${dst_node}" interface "${dst_port}" a ping '
+             'response arrives and TTL is decreased by "${hops}"')
+    def send_ping(nodes_info, src_node, src_port, dst_node, dst_port, hops):
         """Send IPv4 ping and wait for response.
+
+        :param nodes_info: Dictionary containing information on all nodes
+        in topology.
         :param src_node: Source node.
         :param src_port: Source interface.
         :param dst_node: Destination node.
@@ -438,7 +501,8 @@ class IPv4Util(object):
         src_mac = Topology.get_interface_mac(src_node, src_port)
         if dst_node['type'] == NodeType.TG:
             dst_mac = Topology.get_interface_mac(src_node, src_port)
-        adj_int = Topology.get_adjacent_interface(src_node, src_port)
+        _, adj_int = Topology.\
+            get_adjacent_node_and_interface(nodes_info, src_node, src_port)
         first_hop_mac = adj_int['mac_address']
         src_ip = IPv4Util.get_ip_addr(src_node, src_port)
         dst_ip = IPv4Util.get_ip_addr(dst_node, dst_port)
@@ -454,6 +518,7 @@ class IPv4Util(object):
     @keyword('Get IPv4 address of node "${node}" interface "${port}"')
     def get_ip_addr(node, port):
         """Get IPv4 address configured on specified interface
+
         :param node: node dictionary
         :param port: interface name
         :return: IPv4 address of specified interface as a 'str' type
@@ -466,6 +531,7 @@ class IPv4Util(object):
     @keyword('Get IPv4 address prefix of node "${node}" interface "${port}"')
     def get_ip_addr_prefix(node, port):
         """ Get IPv4 address prefix for specified interface.
+
         :param node: Node dictionary.
         :param port: Interface name.
         """
@@ -477,6 +543,7 @@ class IPv4Util(object):
     @keyword('Get IPv4 subnet of node "${node}" interface "${port}"')
     def get_ip_addr_subnet(node, port):
         """ Get IPv4 subnet of specified interface.
+
         :param node: Node dictionary.
         :param port: Interface name.
         """
@@ -488,6 +555,7 @@ class IPv4Util(object):
     @keyword('Flush IPv4 addresses "${port}" "${node}"')
     def flush_ip_addresses(port, node):
         """See IPv4Node.flush_ip_addresses for more information.
+
         :param port:
         :param node:
         :return:
diff --git a/resources/libraries/python/L2Util.py b/resources/libraries/python/L2Util.py
new file mode 100644
index 0000000000..8581b1e879
--- /dev/null
+++ b/resources/libraries/python/L2Util.py
@@ -0,0 +1,119 @@
+# Copyright (c) 2016 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""L2 bridge domain utilities Library."""
+
+from robot.api.deco import keyword
+from resources.libraries.python.topology import Topology
+from resources.libraries.python.VatExecutor import VatExecutor
+
+
+class L2Util(object):
+    """Utilities for l2 bridge domain configuration"""
+
+    def __init__(self):
+        pass
+
+    @staticmethod
+    @keyword('Setup static L2FIB entry on node "${node}" for MAC "${dst_mac}"'
+             ' link "${link}" pair on bd_index "${bd_id}"')
+    def static_l2_fib_entry_via_links(node, dst_mac, link, bd_id):
+        """ Creates a static fib entry on a vpp node
+
+        :param node: node where we wish to add the static fib entry
+        :param dst_mac: destination mac address in the entry
+        :param link: link name of the node destination interface
+        :param bd_id: l2 bridge domain id
+        :type node: dict
+        :type dst_mac: str
+        :type link: str
+        :type bd_id: str
+        """
+        topology = Topology()
+        interface_name = topology.get_interface_by_link_name(node, link)
+        sw_if_index = topology.get_interface_sw_index(node, interface_name)
+        VatExecutor.cmd_from_template(node, "add_l2_fib_entry.vat",
+                                      mac=dst_mac, bd=bd_id,
+                                      interface=sw_if_index)
+
+    @staticmethod
+    @keyword('Setup l2 bridge domain with id "${bd_id}" flooding "${flood}" '
+             'forwarding "${forward}" learning "${learn}" and arp termination '
+             '"${arp_term}" on vpp node "${node}"')
+    def setup_vpp_l2_bridge_domain(node, bd_id, flood, forward, learn,
+                                   arp_term):
+        """Create a l2 bridge domain on the chosen vpp node
+
+        Executes "bridge_domain_add_del bd_id {bd_id} flood {flood} uu-flood 1
+        forward {forward} learn {learn} arp-term {arp_term}" VAT command on
+        the node.
+        For the moment acts as a placeholder
+        :param node: node where we wish to crate the l2 bridge domain
+        :param bd_id: bridge domain id
+        :param flood: enable flooding
+        :param forward: enable forwarding
+        :param learn: enable mac address learning to fib
+        :param arp_term: enable arp_termination
+        :type node: str
+        :type bd_id: str
+        :type flood: bool
+        :type forward: bool
+        :type learn: bool
+        :type arp_term:bool
+        :return:
+        """
+        pass
+
+    @keyword('Add interface "${interface}" to l2 bridge domain with index '
+             '"${bd_id}" and shg "${shg}" on vpp node "${node}"')
+    def add_interface_to_l2_bd(self, node, interface, bd_id, shg):
+        """Adds interface to l2 bridge domain.
+
+        Executes the "sw_interface_set_l2_bridge {interface1} bd_id {bd_id}
+         shg {shg} enable" VAT command on the given node.
+        For the moment acts as a placeholder
+        :param node: node where we want to execute the command that does this.
+        :param interface:
+        :param bd_id:
+        :param shg:
+        :type node: dict
+        :type interface: str
+        :type bd_id: str
+        :type shg: str
+        :return:
+        """
+        pass
+
+    @staticmethod
+    @keyword('Create dict used in bridge domain template file for node '
+             '"${node}" with links "${link_names}" and bd_id "${bd_id}"')
+    def create_bridge_domain_vat_dict(node, link_names, bd_id):
+        """Creates dictionary that can be used in l2 bridge domain template.
+
+        :param node: node data dictionary
+        :param link_names: list of names of links the bridge domain should be
+        connecting
+        :param bd_id: bridge domain index number
+        :type node: dict
+        :type link_names: list
+        :return: dictionary used to generate l2 bridge domain VAT configuration
+        from template file
+        The resulting dictionary looks like this:
+        'interface1': interface name of first interface
+        'interface2': interface name of second interface
+        'bd_id': bridge domian index
+        """
+        bd_dict = Topology().get_interfaces_by_link_names(node, link_names)
+        bd_dict['bd_id'] = bd_id
+        return bd_dict
+
diff --git a/resources/libraries/python/NodePath.py b/resources/libraries/python/NodePath.py
new file mode 100644
index 0000000000..d1aa1f76d4
--- /dev/null
+++ b/resources/libraries/python/NodePath.py
@@ -0,0 +1,192 @@
+# Copyright (c) 2016 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Path utilities library for nodes in the topology."""
+
+from topology import Topology
+
+
+class NodePath(object):
+    """Path utilities for nodes in the topology.
+
+    :Example:
+
+    node1--link1-->node2--link2-->node3--link3-->node2--link4-->node1
+    RobotFramework:
+    | Library | resources/libraries/python/NodePath.py
+
+    | Path test
+    | | [Arguments] | ${node1} | ${node2} | ${node3}
+    | | Append Node | ${nodes1}
+    | | Append Node | ${nodes2}
+    | | Append Nodes | ${nodes3} | ${nodes2}
+    | | Append Node | ${nodes1}
+    | | Compute Path | ${FALSE}
+    | | ${first_int} | ${node}= | First Interface
+    | | ${last_int} | ${node}= | Last Interface
+    | | ${first_ingress} | ${node}= | First Ingress Interface
+    | | ${last_egress} | ${node}= | Last Egress Interface
+    | | ${next} | ${node}= | Next Interface
+
+    Python:
+    >>> from NodePath import NodePath
+    >>> path = NodePath()
+    >>> path.append_node(node1)
+    >>> path.append_node(node2)
+    >>> path.append_nodes(node3, node2)
+    >>> path.append_node(node1)
+    >>> path.compute_path()
+    >>> (interface, node) = path.first_interface()
+    >>> (interface, node) = path.last_interface()
+    >>> (interface, node) = path.first_ingress_interface()
+    >>> (interface, node) = path.last_egress_interface()
+    >>> (interface, node) = path.next_interface()
+    """
+
+    def __init__(self):
+        self._nodes = []
+        self._links = []
+        self._path = []
+        self._path_iter = []
+
+    def append_node(self, node):
+        """Append node to the path.
+
+        :param node: Node to append to the path.
+        :type node: dict
+        """
+        self._nodes.append(node)
+
+    def append_nodes(self, *nodes):
+        """Append nodes to the path.
+
+        :param nodes: Nodes to append to the path.
+        :type nodes: dict
+
+        .. note:: Node order does matter.
+        """
+        for node in nodes:
+            self.append_node(node)
+
+    def clear_path(self):
+        """Clear path."""
+        self._nodes = []
+        self._links = []
+        self._path = []
+        self._path_iter = []
+
+    def compute_path(self, always_same_link=True):
+        """Compute path for added nodes.
+
+        :param always_same_link: If True use always same link between two nodes
+            in path. If False use different link (if available) between two
+            nodes if one link was used before.
+        :type always_same_link: bool
+
+        .. note:: First add at least two nodes to the topology.
+        """
+        nodes = self._nodes
+        if len(nodes) < 2:
+            raise RuntimeError('Not enough nodes to compute path')
+
+        for idx in range(0, len(nodes) - 1):
+            topo = Topology()
+            node1 = nodes[idx]
+            node2 = nodes[idx + 1]
+            links = topo.get_active_connecting_links(node1, node2)
+            if not links:
+                raise RuntimeError('No link between {0} and {1}'.format(
+                    node1['host'], node2['host']))
+
+            link = None
+            l_set = set()
+
+            if always_same_link:
+                l_set = set(links).intersection(self._links)
+            else:
+                l_set = set(links).difference(self._links)
+
+            if not l_set:
+                link = links.pop()
+            else:
+                link = l_set.pop()
+
+            self._links.append(link)
+            interface1 = topo.get_interface_by_link_name(node1, link)
+            interface2 = topo.get_interface_by_link_name(node2, link)
+            self._path.append((interface1, node1))
+            self._path.append((interface2, node2))
+
+        self._path_iter.extend(self._path)
+        self._path_iter.reverse()
+
+    def next_interface(self):
+        """Path interface iterator.
+
+        :return: Interface and node or None if not next interface.
+        :rtype: tuple (str, dict)
+
+        .. note:: Call compute_path before.
+        """
+        if not self._path_iter:
+            return (None, None)
+        else:
+            return self._path_iter.pop()
+
+    def first_interface(self):
+        """Return first interface on the path.
+
+        :return: Interface and node.
+        :rtype: tuple (str, dict)
+
+        .. note:: Call compute_path before.
+        """
+        if not self._path:
+            raise RuntimeError('No path for topology')
+        return self._path[0]
+
+    def last_interface(self):
+        """Return last interface on the path.
+
+        :return: Interface and node.
+        :rtype: tuple (str, dict)
+
+        .. note:: Call compute_path before.
+        """
+        if not self._path:
+            raise RuntimeError('No path for topology')
+        return self._path[-1]
+
+    def first_ingress_interface(self):
+        """Return first ingress interface on the path.
+
+        :return: Interface and node.
+        :rtype: tuple (str, dict)
+
+        .. note:: Call compute_path before.
+        """
+        if not self._path:
+            raise RuntimeError('No path for topology')
+        return self._path[1]
+
+    def last_egress_interface(self):
+        """Return last egress interface on the path.
+
+        :return: Interface and node.
+        :rtype: tuple (str, dict)
+
+        .. note:: Call compute_path before.
+        """
+        if not self._path:
+            raise RuntimeError('No path for topology')
+        return self._path[-2]
diff --git a/resources/libraries/python/PacketVerifier.py b/resources/libraries/python/PacketVerifier.py
index 81798e1f68..54f719fa9a 100644
--- a/resources/libraries/python/PacketVerifier.py
+++ b/resources/libraries/python/PacketVerifier.py
@@ -188,7 +188,7 @@ def packet_reader(interface_name, queue):
 
     buf = ""
     while True:
-        recvd = sock.recv(1500)
+        recvd = sock.recv(1514)
         buf = buf + recvd
 
         pkt = extract_one_packet(buf)
@@ -285,11 +285,7 @@ class Interface(object):
         self.txq.send(pkt)
 
     def recv_pkt(self, timeout=3):
-        while True:
-            pkt = self.rxq.recv(timeout, self.sent_packets)
-            # TODO: FIX FOLLOWING: DO NOT SKIP RARP IN ALL TESTS!!!
-            if pkt.type != 32821:  # Skip RARP packets
-                return pkt
+        return self.rxq.recv(timeout, self.sent_packets)
 
     def close(self):
         self.rxq._proc.terminate()
diff --git a/resources/libraries/python/TrafficScriptExecutor.py b/resources/libraries/python/TrafficScriptExecutor.py
index 2e65a520d0..ee29695812 100644
--- a/resources/libraries/python/TrafficScriptExecutor.py
+++ b/resources/libraries/python/TrafficScriptExecutor.py
@@ -70,8 +70,8 @@ class TrafficScriptExecutor(object):
     def traffic_script_gen_arg(rx_if, tx_if, src_mac, dst_mac, src_ip, dst_ip):
         """Generate traffic script basic arguments string.
 
-           :param rx_if: Interface that sends traffic.
-           :param tx_if: Interface that receives traffic.
+           :param rx_if: Interface that receives traffic.
+           :param tx_if: Interface that sends traffic.
            :param src_mac: Source MAC address.
            :param dst_mac: Destination MAC address.
            :param src_ip: Source IP address.
diff --git a/resources/libraries/python/topology.py b/resources/libraries/python/topology.py
index 522de37d13..2b202e5b4a 100644
--- a/resources/libraries/python/topology.py
+++ b/resources/libraries/python/topology.py
@@ -365,19 +365,25 @@ class Topology(object):
         return None
 
     @staticmethod
-    def get_adjacent_interface(node, interface_name):
-        """Get interface adjacent to specified interface on local network.
-
-           :param node: Node that contains specified interface.
-           :param interface_name: Interface name.
-           :type node: dict
-           :type interface_name: str
-           :return: Return interface or None if not found.
-           :rtype: dict
+    def get_adjacent_node_and_interface(nodes_info, node, interface_name):
+        """Get node and interface adjacent to specified interface
+        on local network.
+
+        :param nodes_info: Dictionary containing information on all nodes
+        in topology.
+        :param node: Node that contains specified interface.
+        :param interface_name: Interface name.
+        :type nodes_info: dict
+        :type node: dict
+        :type interface_name: str
+        :return: Return (node, interface info) tuple or None if not found.
+        :rtype: (dict, dict)
         """
         link_name = None
         # get link name where the interface belongs to
-        for _, port_data in node['interfaces'].iteritems():
+        for port_name, port_data in node['interfaces'].iteritems():
+            if port_name == 'mgmt':
+                continue
             if port_data['name'] == interface_name:
                 link_name = port_data['link']
                 break
@@ -386,7 +392,7 @@ class Topology(object):
             return None
 
         # find link
-        for _, node_data in DICT__nodes.iteritems():
+        for node_data in nodes_info.values():
             # skip self
             if node_data['host'] == node['host']:
                 continue
@@ -395,7 +401,7 @@ class Topology(object):
                 if 'link' not in interface_data:
                     continue
                 if interface_data['link'] == link_name:
-                    return node_data['interfaces'][interface]
+                    return node_data, node_data['interfaces'][interface]
 
     @staticmethod
     def get_interface_pci_addr(node, interface):
@@ -537,3 +543,44 @@ class Topology(object):
         if not interfaces:
             raise RuntimeError('No engress interface for nodes')
         return interfaces[0]
+
+    @keyword('Get link data useful in circular topology test from tg "${tgen}"'
+             ' dut1 "${dut1}" dut2 "${dut2}"')
+    def get_links_dict_from_nodes(self, tgen, dut1, dut2):
+        """Returns link combinations used in tests in circular topology.
+
+        For the time being it returns links from the Node path:
+        TG->DUT1->DUT2->TG
+        :param tg: traffic generator node data
+        :param dut1: DUT1 node data
+        :param dut2: DUT2 node data
+        :type tg: dict
+        :type dut1: dict
+        :type dut2: dict
+        :return: dictionary of possible link combinations
+        the naming convention until changed to something more general is
+        implemented is this:
+        DUT1_DUT2_LINK: link name between DUT! and DUT2
+        DUT1_TG_LINK: link name between DUT1 and TG
+        DUT2_TG_LINK: link name between DUT2 and TG
+        TG_TRAFFIC_LINKS: list of link names that generated traffic is sent
+        to and from
+        DUT1_BD_LINKS: list of link names that will be connected by the bridge
+        domain on DUT1
+        DUT2_BD_LINKS: list of link names that will be connected by the bridge
+        domain on DUT2
+        """
+        # TODO: replace with generic function.
+        dut1_dut2_link = self.get_first_active_connecting_link(dut1, dut2)
+        dut1_tg_link = self.get_first_active_connecting_link(dut1, tgen)
+        dut2_tg_link = self.get_first_active_connecting_link(dut2, tgen)
+        tg_traffic_links = [dut1_tg_link, dut2_tg_link]
+        dut1_bd_links = [dut1_dut2_link, dut1_tg_link]
+        dut2_bd_links = [dut1_dut2_link, dut2_tg_link]
+        topology_links = {'DUT1_DUT2_LINK': dut1_dut2_link,
+                          'DUT1_TG_LINK': dut1_tg_link,
+                          'DUT2_TG_LINK': dut2_tg_link,
+                          'TG_TRAFFIC_LINKS': tg_traffic_links,
+                          'DUT1_BD_LINKS': dut1_bd_links,
+                          'DUT2_BD_LINKS': dut2_bd_links}
+        return topology_links