Add VIRL server-side framework and topology templates.

Change-Id: I02e7f85e3259dc0a5b2c7d0098747921a75fa5ea
Signed-off-by: Carsten Koester <ckoester@cisco.com>

6 files changed, 791 insertions, 0 deletions

diff --git a/resources/tools/virl/README.md b/resources/tools/virl/README.md
new file mode 100644
index 0000000000..fe4edd8853
--- /dev/null
+++ b/resources/tools/virl/README.md
@@ -0,0 +1,18 @@
+## VIRL scripts
+
+This directory, and subdirectories, contain files required for automated VIRL testing. These files
+are based on the following assumptions:
+
+  - Files in this directory are installed on the VIRL server host, and scripts in bin/ directory
+    are executable by the user used in the bootstrap.sh script in the root directory of this
+    project
+
+  - the VIRL server has a "server" image, as well as a "vPP" image that is accepting a cloud-init
+    configuration and is ready to receive a VPP upgrade.
+
+  - the VIRL server has an NFS export that can be mounted by VIRL VMs, or there is an NFS server
+    with an export mounted by the VIRL server and mountable by VIRL VMs.
+
+  - the bin/start_testcase script has hardcoded default values both in variable assignments
+    near the beginning of the file, as well as in "parser.add_argument", "default=" options.
+    These may need to be updated.
diff --git a/resources/tools/virl/bin/kill-idle-testcases b/resources/tools/virl/bin/kill-idle-testcases
new file mode 100755
index 0000000000..39a7961ba2
--- /dev/null
+++ b/resources/tools/virl/bin/kill-idle-testcases
@@ -0,0 +1,29 @@
+#!/bin/bash
+
+# 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.
+
+IDLE_THRESHOLD=3600 # 1 hour
+
+CURR_TIME=$(date +%s)
+for s in /nfs/scratch/*
+do
+  s_time=$(cat $s/start_time)
+  age=$[$CURR_TIME - $s_time]
+  s2=$(basename $s)
+  if [ $age -gt $IDLE_THRESHOLD ]
+  then
+    echo "Simulation $s is older than $IDLE_THRESHOLD seconds (age $age), killing it..."
+    stop-testcase $s2
+  fi
+done
diff --git a/resources/tools/virl/bin/start-testcase b/resources/tools/virl/bin/start-testcase
new file mode 100755
index 0000000000..e532ec7ef3
--- /dev/null
+++ b/resources/tools/virl/bin/start-testcase
@@ -0,0 +1,361 @@
+#!/usr/bin/python
+
+# 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.
+
+__author__ = 'ckoester@cisco.com'
+
+import sys
+import requests
+import re
+import os
+import argparse
+import tempfile
+import shutil
+import time
+import paramiko
+
+#
+# Helper function to indent a text string
+#
+def indent(lines, amount, fillchar=' '):
+    padding = amount * fillchar
+    return padding + ('\n'+padding).join(lines.split('\n'))
+
+#
+# Main function.
+# FIXME: Right now, this is really coded like a shell script, as one big
+# function executed in sequence. This should be broken down into multiple
+# functions.
+#
+def main():
+    #
+    # Verify CLI parameters and try to download our VPP image into a temporary
+    # file first
+    #
+    parser = argparse.ArgumentParser()
+    parser.add_argument("topology", help="the base topology to be started")
+    parser.add_argument("packages", help="Path to the VPP .deb(s) that " +
+                        "is/are to be installed", nargs='+')
+    parser.add_argument("-c", "--copy", help="Copy the .deb packages, " +
+                        "leaving the originals in place. Default is to " +
+                        "move them.", action='store_true')
+    parser.add_argument("-k", "--keep", help="Keep (do not delete) the " +
+                        "simulation in case of error", action='store_true')
+    parser.add_argument("-v", "--verbosity", action="count", default=0)
+    # FIXME: THe default value for the following line should not be a hardcoded
+    # address. We should determine it dynamically (e.g. IP address of first
+    # interface or whichever interface is tied to the flat network)
+    parser.add_argument("-nip", "--nfs-server-ip", help="NFS server (our) IP",
+                        default="10.30.51.28")
+    parser.add_argument("-ns", "--nfs-scratch-directory",
+                        help="Server location for NFS scratch diretory",
+                        default="/nfs/scratch")
+    parser.add_argument("-nc", "--nfs-common-directory",
+                        help="Server location for NFS common (read-only) " +
+                        "directory", default="/nfs/common")
+    parser.add_argument("-wc", "--wait-count",
+                        help="number of intervals to wait for simulation to " +
+                        "be ready", type=int, default=12)
+    parser.add_argument("-wt", "--wait-time",
+                        help="length of a single interval to wait for " +
+                        "simulation to be ready", type=int, default=5)
+    parser.add_argument("-vip", "--virl-ip",
+                        help="VIRL IP and Port (e.g. 127.0.0.1:19399)",
+                        default="127.0.0.1:19399")
+    parser.add_argument("-u", "--username", help="VIRL username",
+                        default="tb4-virl")
+    parser.add_argument("-p", "--password", help="VIRL password",
+                        default="Cisco1234")
+    parser.add_argument("-su", "--ssh-user", help="SSH username",
+                        default="cisco")
+    parser.add_argument("-spr", "--ssh-privkey", help="SSH private keyfile",
+                        default="/home/jenkins-in/.ssh/id_rsa_virl")
+    parser.add_argument("-spu", "--ssh-pubkey", help="SSH public keyfile",
+                        default="/home/jenkins-in/.ssh/id_rsa_virl.pub")
+    parser.add_argument("--topology-directory", help="Topology directory",
+                        default="/home/jenkins-in/testcase-infra/topologies")
+
+    args = parser.parse_args()
+
+    #
+    # Check if topology and template exist
+    #
+    if args.verbosity >= 2:
+        print "DEBUG: Running with topology {}".format(args.topology)
+
+    topology_virl_filename = os.path.join(args.topology_directory,
+                                          args.topology + ".virl")
+    topology_yaml_filename = os.path.join(args.topology_directory,
+                                          args.topology + ".yaml")
+
+    if not os.path.isfile(topology_virl_filename):
+        print "ERROR: Topology VIRL file {} does not exist".\
+            format(topology_virl_filename)
+        sys.exit(1)
+    if not os.path.isfile(topology_yaml_filename):
+        print "ERROR: Topology YAML file {} does not exist".\
+            format(topology_yaml_filename)
+        sys.exit(1)
+
+    #
+    # Check if VPP package exists
+    #
+    for package in args.packages:
+        if args.verbosity >= 2:
+            print "DEBUG: Checking if file {} exists".format(package)
+        if not os.path.isfile(package):
+            print "ERROR: Debian package {} does not exist.".format(package)
+            sys.exit(1)
+
+    #
+    # Start VIRL topology
+    #
+    if args.verbosity >= 1:
+        print "DEBUG: Starting VIRL topology"
+    temp_handle, temp_topology = tempfile.mkstemp()
+    with open(args.ssh_pubkey, 'r') as pubkey_file:
+        pub_key = pubkey_file.read().replace('\n', '')
+    with open(temp_topology, 'w') as new_file, \
+        open(topology_virl_filename, 'r') as old_file:
+        for line in old_file:
+            line = line.replace("  - VIRL-USER-SSH-PUBLIC-KEY", "  - "+pub_key)
+            line = line.replace("$$NFS_SERVER_SCRATCH$$", \
+                args.nfs_server_ip+":"+args.nfs_scratch_directory)
+            line = line.replace("$$NFS_SERVER_COMMON$$", \
+                args.nfs_server_ip+":"+args.nfs_common_directory)
+            new_file.write(line)
+    os.close(temp_handle)
+
+    try:
+        new_file = open(temp_topology, 'rb')
+        headers = {'Content-Type': 'text/xml'}
+        req = requests.post('http://' + args.virl_ip + '/simengine/rest/launch',
+                            headers=headers,
+                            auth=(args.username, args.password), data=new_file)
+        if args.verbosity >= 2:
+            print "DEBUG: - Response Code {}".format(req.status_code)
+        new_file.close()
+
+    except:
+        print "ERROR: Launching VIRL simulation - received invalid response"
+        print req
+        os.remove(temp_topology)
+        sys.exit(1)
+
+    if req.status_code != 200:
+        print "ERROR: Launching VIRL simulation - received status other " + \
+            "than 200 HTTP OK"
+        print "Status was: {} \n".format(req.status_code)
+        print "Response content was: "
+        print req.content
+        os.remove(temp_topology)
+        sys.exit(1)
+
+    # If we got here, we had a good response. The response content is the
+    # session ID.
+    session_id = req.content
+
+    #
+    # Create simulation scratch directory. Move topology file into that
+    # directory. Copy or move debian packages into that directory.
+    #
+    scratch_directory = os.path.join(args.nfs_scratch_directory, session_id)
+    os.mkdir(scratch_directory)
+    shutil.move(temp_topology, os.path.join(scratch_directory,
+                                            "virl_topology.virl"))
+    os.mkdir(os.path.join(scratch_directory, "vpp"))
+    for package in args.packages:
+        if args.copy:
+            shutil.copy(package, os.path.join(scratch_directory, "vpp",
+                                              os.path.basename(package)))
+        else:
+            shutil.move(package, os.path.join(scratch_directory, "vpp",
+                                              os.path.basename(package)))
+
+    #
+    # Wait for simulation to become active
+    #
+    if args.verbosity >= 1:
+        print "DEBUG: Waiting for simulation to become active"
+
+    sim_is_started = False
+    nodelist = []
+
+    count = args.wait_count
+    while (count > 0) and not sim_is_started:
+        time.sleep(args.wait_time)
+        count -= 1
+
+        req = requests.get('http://' + args.virl_ip + '/simengine/rest/nodes/' +
+                           session_id, auth=(args.username, args.password))
+        data = req.json()
+
+        active = 0
+        total = 0
+
+        # Flush the node list every time, keep the last one
+        nodelist = []
+
+        # Hosts are the keys of the inner dictionary
+        for key in data[session_id].keys():
+            if data[session_id][key]['management-proxy'] == "self":
+                continue
+            nodelist.append(key)
+            total += 1
+            if data[session_id][key]['state'] == "ACTIVE":
+                active += 1
+        if args.verbosity >= 2:
+            print "DEBUG: - Attempt {} out of {}, total {} hosts, {} active".\
+                format(args.wait_count-count, args.wait_count, total, active)
+        if active == total:
+            sim_is_started = True
+
+    if not sim_is_started:
+        print "ERROR: Simulation started OK but devices never changed to " + \
+            "ACTIVE state"
+        print "Last VIRL response:"
+        print data
+        if not args.keep:
+            shutil.rmtree(scratch_directory)
+            req = requests.get('http://' + args.virl_ip +
+                               '/simengine/rest/stop/' + session_id,
+                               auth=(args.username, args.password))
+
+    if args.verbosity >= 2:
+        print "DEBUG: Nodes: " + ", ".join(nodelist)
+
+    #
+    # Fetch simulation's IPs and create files
+    # (ansible hosts file, topology YAML file)
+    #
+    req = requests.get('http://' + args.virl_ip +
+                       '/simengine/rest/interfaces/' + session_id +
+                       '?fetch-state=1', auth=(args.username, args.password))
+    data = req.json()
+
+    # Populate node addresses
+    nodeaddrs = {}
+    topology = {}
+    for key in nodelist:
+        nodetype = re.split('[0-9]', key)[0]
+        if not nodetype in nodeaddrs:
+            nodeaddrs[nodetype] = {}
+        nodeaddrs[nodetype][key] = re.split('\\/', \
+            data[session_id][key]['management']['ip-address'])[0]
+        if args.verbosity >= 2:
+            print "DEBUG: Node {} is of type {} and has management IP {}".\
+                format(key, nodetype, nodeaddrs[nodetype][key])
+
+        topology[key] = {}
+        for key2 in data[session_id][key]:
+            topology[key]["nic-"+key2] = data[session_id][key][key2]
+            if 'ip-address' in topology[key]["nic-"+key2]:
+                topology[key]["nic-"+key2]['ip-addr'] = re.split('\\/', \
+                    topology[key]["nic-"+key2]['ip-address'])[0]
+
+    # Write ansible file
+    ansiblehosts = open(os.path.join(scratch_directory, 'ansible-hosts'), 'w')
+    for key1 in nodeaddrs:
+        ansiblehosts.write("[{}]\n".format(key1))
+        for key2 in nodeaddrs[key1]:
+            ansiblehosts.write("{} hostname={}\n".format(nodeaddrs[key1][key2],
+                                                         key2))
+    ansiblehosts.close()
+
+    # Process topology YAML template
+    with open(args.ssh_privkey, 'r') as privkey_file:
+        priv_key = indent(privkey_file.read(), 6)
+
+    with open(os.path.join(scratch_directory, "topology.yaml"), 'w') as \
+        new_file, open(topology_yaml_filename, 'r') as old_file:
+        for line in old_file:
+            new_file.write(line.format(priv_key=priv_key, topology=topology))
+
+    #
+    # Wait for hosts to become reachable over SSH
+    #
+    if args.verbosity >= 1:
+        print "DEBUG: Waiting for hosts to become reachable using SSH"
+
+    missing = -1
+    count = args.wait_count
+    while (count > 0) and missing != 0:
+        time.sleep(args.wait_time)
+        count -= 1
+
+        missing = 0
+        for key in nodelist:
+            if not os.path.exists(os.path.join(scratch_directory, key)):
+                missing += 1
+        if args.verbosity >= 2:
+            print "DEBUG: - Attempt {} out of {}, waiting for {} hosts".\
+                format(args.wait_count-count, args.wait_count, missing)
+
+    if missing != 0:
+        print "ERROR: Simulation started OK but {} hosts ".format(missing) + \
+            "never mounted their NFS directory"
+        if not args.keep:
+            shutil.rmtree(scratch_directory)
+            req = requests.get('http://' + args.virl_ip +
+                               '/simengine/rest/stop/' + session_id,
+                               auth=(args.username, args.password))
+
+    #
+    # Upgrade VPP
+    #
+    if args.verbosity >= 1:
+        print "DEBUG: Uprading VPP"
+
+    for key1 in nodeaddrs:
+        if not key1 == 'tg':
+            for key2 in nodeaddrs[key1]:
+                ipaddr = nodeaddrs[key1][key2]
+                if args.verbosity >= 2:
+                    print "DEBUG: Upgrading VPP on node {}".format(ipaddr)
+                paramiko.util.log_to_file(os.path.join(scratch_directory,
+                                                       "ssh.log"))
+                client = paramiko.SSHClient()
+                client.load_system_host_keys()
+                client.load_host_keys("/dev/null")
+                client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+                client.connect(ipaddr, username=args.ssh_user,
+                               key_filename=args.ssh_privkey)
+                stdin, stdout, stderr = \
+                    client.exec_command('sudo dpkg -i /scratch/vpp/*deb')
+                c_stdout = stdout.read()
+                c_stderr = stderr.read()
+                if args.verbosity >= 2:
+                    print "DEBUG: Command output was:"
+                    print c_stdout
+                    print "DEBUG: Command stderr was:"
+                    print c_stderr
+
+    #
+    # Write a file with timestamp to scratch directory. We can use this to track
+    # how long a simulation has been running.
+    #
+    with open(os.path.join(scratch_directory, 'start_time'), 'a') as \
+        timestampfile:
+        timestampfile.write('{}\n'.format(int(time.time())))
+
+    #
+    # Declare victory
+    #
+    if args.verbosity >= 1:
+        print "SESSION ID: {}".format(session_id)
+
+    print "{}".format(session_id)
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/resources/tools/virl/bin/stop-testcase b/resources/tools/virl/bin/stop-testcase
new file mode 100755
index 0000000000..dbbb53e30f
--- /dev/null
+++ b/resources/tools/virl/bin/stop-testcase
@@ -0,0 +1,24 @@
+#!/bin/bash
+
+# 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.
+
+VIRL_USER="tb4-virl"                                            # VIRL credentials (what one would enter in VMMaestro)
+VIRL_PASSWORD="Cisco1234"
+
+NFS_SCRATCH_SERVERDIR="/nfs/scratch"                            # Our own (NFS server) IP address, and directory locations.
+
+TESTCASE=$1
+
+virl_std_client -u $VIRL_USER -p $VIRL_PASSWORD simengine-stop --session-id $TESTCASE
+rm -fr ${NFS_SCRATCH_SERVERDIR}/${TESTCASE}
diff --git a/resources/tools/virl/topologies/simple-ring.virl b/resources/tools/virl/topologies/simple-ring.virl
new file mode 100644
index 0000000000..04babe5e99
--- /dev/null
+++ b/resources/tools/virl/topologies/simple-ring.virl
@@ -0,0 +1,300 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<topology xmlns="http://www.cisco.com/VIRL" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" schemaVersion="0.9" xsi:schemaLocation="http://www.cisco.com/VIRL https://raw.github.com/CiscoVIRL/schema/v0.9/virl.xsd">
+    <extensions>
+        <entry key="management_network" type="String">flat</entry>
+    </extensions>
+    <node name="tg1" type="SIMPLE" subtype="server" location="570,238" vmImage="server-java">
+        <extensions>
+            <entry key="config" type="String">#cloud-config&#xD;
+bootcmd:&#xD;
+- ln -s -t /etc/rc.d /etc/rc.local&#xD;
+hostname: tg1&#xD;
+manage_etc_hosts: true&#xD;
+nfs_server_scratch: $$NFS_SERVER_SCRATCH$$
+nfs_server_common: $$NFS_SERVER_COMMON$$
+runcmd:&#xD;
+- start ttyS0&#xD;
+- systemctl start getty@ttyS0.service&#xD;
+- systemctl start rc-local&#xD;
+- touch /tmp/before-sed&#xD;
+- sed -i 's/^\s*PasswordAuthentication\s\+no/PasswordAuthentication yes/' /etc/ssh/sshd_config&#xD;
+- echo "UseDNS no" &gt;&gt; /etc/ssh/sshd_config&#xD;
+- service ssh restart&#xD;
+- service sshd restart&#xD;
+users:&#xD;
+- default&#xD;
+- gecos: User configured by VIRL Configuration Engine 0.21.4&#xD;
+  lock-passwd: false&#xD;
+  name: cisco&#xD;
+  plain-text-passwd: cisco&#xD;
+  shell: /bin/bash&#xD;
+  ssh-authorized-keys:&#xD;
+  - VIRL-USER-SSH-PUBLIC-KEY&#xD;
+  - VIRL-USER-SSH-PUBLIC-KEY&#xD;
+  sudo: ALL=(ALL) NOPASSWD:ALL&#xD;
+write_files:&#xD;
+- path: /etc/init/ttyS0.conf&#xD;
+  owner: root:root&#xD;
+  content: |&#xD;
+    # ttyS0 - getty&#xD;
+    # This service maintains a getty on ttyS0 from the point the system is&#xD;
+    # started until it is shut down again.&#xD;
+    start on stopped rc or RUNLEVEL=[12345]&#xD;
+    stop on runlevel [!12345]&#xD;
+    respawn&#xD;
+    exec /sbin/getty -L 115200 ttyS0 vt102&#xD;
+  permissions: '0644'&#xD;
+- path: /etc/systemd/system/dhclient@.service&#xD;
+  content: |&#xD;
+    [Unit]&#xD;
+    Description=Run dhclient on %i interface&#xD;
+    After=network.target&#xD;
+    [Service]&#xD;
+    Type=oneshot&#xD;
+    ExecStart=/sbin/dhclient %i -pf /var/run/dhclient.%i.pid -lf /var/lib/dhclient/dhclient.%i.lease&#xD;
+    RemainAfterExit=yes&#xD;
+  owner: root:root&#xD;
+  permissions: '0644'&#xD;
+- path: /usr/local/sbin/cloud-instance-name
+  content: |
+    #!/usr/bin/python
+    import pickle
+    print pickle.loads(open('/var/lib/cloud/instance/obj.pkl').read()).metadata['name']
+  owner: root:root
+  permissions: '0755'
+- path: /etc/rc.local&#xD;
+  owner: root:root&#xD;
+  permissions: '0755'&#xD;
+  content: |-&#xD;
+    #!/bin/sh&#xD;
+    ifconfig eth1 up 10.0.0.6 netmask 255.255.255.252&#xD;
+    ifconfig eth2 up 10.0.0.14 netmask 255.255.255.252&#xD;
+
+    grep -q nfs_server_scratch /var/lib/cloud/instance/user-data.txt || exit 1
+    grep -q nfs_server_common /var/lib/cloud/instance/user-data.txt || exit 1
+    nfs_server_scratch=$(grep -E '^nfs_server_scratch:' /var/lib/cloud/instance/user-data.txt | awk '{ print $2 }')
+    nfs_server_common=$(grep -E '^nfs_server_common:' /var/lib/cloud/instance/user-data.txt | awk '{ print $2 }')
+    instance_name=$(/usr/local/sbin/cloud-instance-name | cut -f 3 -d '&lt;' | cut -f 1 -d '&gt;')
+    echo My instance name is $instance_name
+
+    MAXCOUNT=12
+    RETRY=5
+
+    mkdir -p /scratch
+    mkdir -p /mnt/common
+
+    echo "Mounting NFS directories"
+    count=0
+    while [ $count -lt $MAXCOUNT ] &amp;&amp; ! mount -t nfs "${nfs_server_scratch}/${instance_name}" /scratch
+    do
+      sleep 5
+      count=$[$count+1]
+    done
+
+    mount -t nfs "${nfs_server_common}" /mnt/common
+
+    mkdir /scratch/$(hostname)
+
+    exit 0&#xD;
+</entry>
+            <entry key="Auto-generate config" type="Boolean">false</entry>
+        </extensions>
+        <interface id="0" name="eth1" ipv4="10.0.0.6" netPrefixLenV4="30"/>
+        <interface id="1" name="eth2" ipv4="10.0.0.14" netPrefixLenV4="30"/>
+    </node>
+    <node name="sut1" type="SIMPLE" subtype="vPP" location="425,26"  vmImage="server-java">
+        <extensions>
+            <entry key="config" type="string">#cloud-config
+bootcmd:
+- ln -s -t /etc/rc.d /etc/rc.local
+hostname: sut1
+manage_etc_hosts: true
+nfs_server_scratch: $$NFS_SERVER_SCRATCH$$
+nfs_server_common: $$NFS_SERVER_COMMON$$
+runcmd:
+- start ttyS0
+- systemctl start getty@ttyS0.service
+- systemctl start rc-local
+- sed -i '/^\s*PasswordAuthentication\s\+no/d' /etc/ssh/sshd_config
+- echo "UseDNS no" &gt;&gt; /etc/ssh/sshd_config
+- service ssh restart
+- service sshd restart
+- sed -i 's/no-pci//' /opt/cisco/vpe/etc/qn.conf
+- sed -i 's/1024/1024 decimal-interface-names/g' /opt/cisco/vpe/etc/qn.conf
+users:
+- default
+- gecos: User configured by VIRL Configuration Engine 0.21.4
+  lock-passwd: false
+  name: cisco
+  plain-text-passwd: cisco
+  shell: /bin/bash
+  ssh-authorized-keys:
+  - VIRL-USER-SSH-PUBLIC-KEY
+  - VIRL-USER-SSH-PUBLIC-KEY
+  sudo: ALL=(ALL) NOPASSWD:ALL
+write_files:
+- path: /etc/init/ttyS0.conf
+  owner: root:root
+  content: |
+    # ttyS0 - getty
+    # This service maintains a getty on ttyS0 from the point the system is
+    # started until it is shut down again.
+    start on stopped rc or RUNLEVEL=[12345]
+    stop on runlevel [!12345]
+    respawn
+    exec /sbin/getty -L 115200 ttyS0 vt102
+  permissions: '0644'
+- path: /etc/systemd/system/dhclient@.service
+  content: |
+    [Unit]
+    Description=Run dhclient on %i interface
+    After=network.target
+    [Service]
+    Type=oneshot
+    ExecStart=/sbin/dhclient %i -pf /var/run/dhclient.%i.pid -lf /var/lib/dhclient/dhclient.%i.lease
+    RemainAfterExit=yes
+  owner: root:root
+  permissions: '0644'
+- path: /usr/local/sbin/cloud-instance-name
+  content: |
+    #!/usr/bin/python
+    import pickle
+    print pickle.loads(open('/var/lib/cloud/instance/obj.pkl').read()).metadata['name']
+  owner: root:root
+  permissions: '0755'
+- path: /etc/rc.local&#xD;
+  owner: root:root&#xD;
+  permissions: '0755'&#xD;
+  content: |-&#xD;
+    #!/bin/sh&#xD;
+    grep -q nfs_server_scratch /var/lib/cloud/instance/user-data.txt || exit 1
+    grep -q nfs_server_common /var/lib/cloud/instance/user-data.txt || exit 1
+    nfs_server_scratch=$(grep -E '^nfs_server_scratch:' /var/lib/cloud/instance/user-data.txt | awk '{ print $2 }')
+    nfs_server_common=$(grep -E '^nfs_server_common:' /var/lib/cloud/instance/user-data.txt | awk '{ print $2 }')
+    instance_name=$(/usr/local/sbin/cloud-instance-name | cut -f 3 -d '&lt;' | cut -f 1 -d '&gt;')
+    echo My instance name is $instance_name
+
+    MAXCOUNT=12
+    RETRY=5
+
+    mkdir -p /scratch
+    mkdir -p /mnt/common
+
+    echo "Mounting NFS directories"
+    count=0
+    while [ $count -lt $MAXCOUNT ] &amp;&amp; ! mount -t nfs "${nfs_server_scratch}/${instance_name}" /scratch
+    do
+      sleep 5
+      count=$[$count+1]
+    done
+
+    mount -t nfs "${nfs_server_common}" /mnt/common
+
+    mkdir /scratch/$(hostname)
+
+    exit 0&#xD;
+</entry>
+        </extensions>
+        <interface id="0" name="GigabitEthernet0/4/0" ipv4="10.0.0.9" netPrefixLenV4="30"/>
+        <interface id="1" name="GigabitEthernet0/5/0" ipv4="10.0.0.5" netPrefixLenV4="30"/>
+    </node>
+    <node name="sut2" type="SIMPLE" subtype="vPP" location="748,26" vmImage="server-java">
+        <extensions>
+            <entry key="config" type="string">#cloud-config
+bootcmd:
+- ln -s -t /etc/rc.d /etc/rc.local
+hostname: sut2
+manage_etc_hosts: true
+nfs_server_scratch: $$NFS_SERVER_SCRATCH$$
+nfs_server_common: $$NFS_SERVER_COMMON$$
+runcmd:
+- start ttyS0
+- systemctl start getty@ttyS0.service
+- systemctl start rc-local
+- sed -i '/^\s*PasswordAuthentication\s\+no/d' /etc/ssh/sshd_config
+- echo "UseDNS no" &gt;&gt; /etc/ssh/sshd_config
+- service ssh restart
+- service sshd restart
+- sed -i 's/no-pci//' /opt/cisco/vpe/etc/qn.conf
+- sed -i 's/1024/1024 decimal-interface-names/g' /opt/cisco/vpe/etc/qn.conf
+users:
+- default
+- gecos: User configured by VIRL Configuration Engine 0.21.4
+  lock-passwd: false
+  name: cisco
+  plain-text-passwd: cisco
+  shell: /bin/bash
+  ssh-authorized-keys:
+  - VIRL-USER-SSH-PUBLIC-KEY
+  - VIRL-USER-SSH-PUBLIC-KEY
+  sudo: ALL=(ALL) NOPASSWD:ALL
+write_files:
+- path: /etc/init/ttyS0.conf
+  owner: root:root
+  content: |
+    # ttyS0 - getty
+    # This service maintains a getty on ttyS0 from the point the system is
+    # started until it is shut down again.
+    start on stopped rc or RUNLEVEL=[12345]
+    stop on runlevel [!12345]
+    respawn
+    exec /sbin/getty -L 115200 ttyS0 vt102
+  permissions: '0644'
+- path: /etc/systemd/system/dhclient@.service
+  content: |
+    [Unit]
+    Description=Run dhclient on %i interface
+    After=network.target
+    [Service]
+    Type=oneshot
+    ExecStart=/sbin/dhclient %i -pf /var/run/dhclient.%i.pid -lf /var/lib/dhclient/dhclient.%i.lease
+    RemainAfterExit=yes
+  owner: root:root
+  permissions: '0644'
+- path: /usr/local/sbin/cloud-instance-name
+  content: |
+    #!/usr/bin/python
+    import pickle
+    print pickle.loads(open('/var/lib/cloud/instance/obj.pkl').read()).metadata['name']
+  owner: root:root
+  permissions: '0755'
+- path: /etc/rc.local&#xD;
+  owner: root:root&#xD;
+  permissions: '0755'&#xD;
+  content: |-&#xD;
+    #!/bin/sh&#xD;
+    grep -q nfs_server_scratch /var/lib/cloud/instance/user-data.txt || exit 1
+    grep -q nfs_server_common /var/lib/cloud/instance/user-data.txt || exit 1
+    nfs_server_scratch=$(grep -E '^nfs_server_scratch:' /var/lib/cloud/instance/user-data.txt | awk '{ print $2 }')
+    nfs_server_common=$(grep -E '^nfs_server_common:' /var/lib/cloud/instance/user-data.txt | awk '{ print $2 }')
+    instance_name=$(/usr/local/sbin/cloud-instance-name | cut -f 3 -d '&lt;' | cut -f 1 -d '&gt;')
+    echo My instance name is $instance_name
+
+    MAXCOUNT=12
+    RETRY=5
+
+    mkdir -p /scratch
+    mkdir -p /mnt/common
+
+    echo "Mounting NFS directories"
+    count=0
+    while [ $count -lt $MAXCOUNT ] &amp;&amp; ! mount -t nfs "${nfs_server_scratch}/${instance_name}" /scratch
+    do
+      sleep 5
+      count=$[$count+1]
+    done
+
+    mount -t nfs "${nfs_server_common}" /mnt/common
+
+    mkdir /scratch/$(hostname)
+
+    exit 0&#xD;
+</entry>
+        </extensions>
+        <interface id="0" name="GigabitEthernet0/4/0" ipv4="10.0.0.13" netPrefixLenV4="30"/>
+        <interface id="1" name="GigabitEthernet0/5/0" ipv4="10.0.0.10" netPrefixLenV4="30"/>
+    </node>
+    <connection dst="/virl:topology/virl:node[1]/virl:interface[2]" src="/virl:topology/virl:node[3]/virl:interface[1]"/>
+    <connection dst="/virl:topology/virl:node[2]/virl:interface[2]" src="/virl:topology/virl:node[1]/virl:interface[1]"/>
+    <connection dst="/virl:topology/virl:node[3]/virl:interface[2]" src="/virl:topology/virl:node[2]/virl:interface[1]"/>
+</topology>
diff --git a/resources/tools/virl/topologies/simple-ring.yaml b/resources/tools/virl/topologies/simple-ring.yaml
new file mode 100644
index 0000000000..094adf3988
--- /dev/null
+++ b/resources/tools/virl/topologies/simple-ring.yaml
@@ -0,0 +1,59 @@
+---
+metadata:
+  version: 0.1
+  schema:
+    - resources/topology_schemas/3_node_topology.sch.yaml
+    - resources/topology_schemas/topology.sch.yaml
+  tags: [hw, 3-node]
+
+nodes:
+  TG:
+    type: TG
+    host: "{topology[tg1][nic-management][ip-addr]}"
+    port: 22
+    username: cisco
+    priv_key: |
+{priv_key}
+    interfaces:
+      port3:
+        mac_address: "{topology[tg1][nic-0][hw-addr]}"
+        pci_address: "0000:00:04.0"
+        link: link1
+        driver: virtio-pci
+      port5:
+        mac_address: "{topology[tg1][nic-1][hw-addr]}"
+        pci_address: "0000:00:05.0"
+        link: link2
+        driver: virtio-pci
+  DUT1:
+    type: DUT
+    host: "{topology[sut1][nic-management][ip-addr]}"
+    port: 22
+    username: cisco
+    priv_key: |
+{priv_key}
+    interfaces:
+      port3:
+        mac_address: "{topology[sut1][nic-0][hw-addr]}"
+        pci_address: "0000:00:04.0"
+        link: link3
+      port1:
+        mac_address: "{topology[sut1][nic-1][hw-addr]}"
+        pci_address: "0000:00:05.0"
+        link: link1
+  DUT2:
+    type: DUT
+    host: "{topology[sut2][nic-management][ip-addr]}"
+    port: 22
+    username: cisco
+    priv_key: |
+{priv_key}
+    interfaces:
+      port1:
+        mac_address: "{topology[sut2][nic-0][hw-addr]}"
+        pci_address: "0000:00:04.0"
+        link: link2
+      port3:
+        mac_address: "{topology[sut2][nic-1][hw-addr]}"
+        pci_address: "0000:00:05.0"
+        link: link3