diff --git a/README.md b/README.md
index bbd7c84..63ac970 100644
--- a/README.md
+++ b/README.md
@@ -1,8 +1,18 @@
 # Overview
 
-Magpie is a charm used for testing the networking (ICMP and DNS specifically)
-of a juju provider/substrate. Simply deploy more than one Magpie charm and 
-watch the status messages and debug logs. 
+Magpie is a charm used for testing the networking of a juju provider/substrate.
+Simply deploy more than one Magpie charm and watch the status messages and
+debug logs. 
+
+Magpie will test:
+
+ - DNS functionality
+ - Local hostname lookup
+ - ICMP between peers
+ - MTU between leader and clients
+ - Transfer between leader and clients
+
+*MTU and transfer speed are tested with iperf2*
 
 Status messages will show the unit numbers that have issues - if there are 
 no problems, there will not be a verbose status message.
@@ -10,6 +20,13 @@ no problems, there will not be a verbose status message.
 All actions, strings, queries and actions are logged in the juju logs.
 
 
+# MTU Notes
+
+The MTU size reported by iperf is sometimes 8 or 12 bytes less than the configured
+MTU on the interface. This is due to TCP options not being included in the measurement,
+and therefore we ignore that difference and report everything OK.
+
+
 # Workload Status
 
 In addition to ICMP and DNS status messages, if a networking problem is
@@ -26,12 +43,15 @@ relation.
 * **`magpie-dns.failed`** DNS has failed to one or more units in the peer 
 relation.
 
+Note: work stopped on these states as it is currently unlikely magpie will be consumed
+as a layer.
+Please open an issue against this github repo if more states are required.
 
 # Usage
 
 ```
 juju deploy magpie -n 2
-juju deploy magpie -n 1 --to lxc:1
+juju deploy magpie -n 1 --to lxd:1
 ```
 
 This charm also supports the following config values:
@@ -61,8 +81,21 @@ This charm also supports the following config values:
     default: 1
     description: Number of ICMP packets per ping
     type: int
+  required_mtu:
+    default: 0
+    description: |
+        Desired MTU for all nodes - block if the unit MTU is different 
+        (accounting for encapsulation). 0 disables.
+    type: int
+  min_speed:
+    default: 0
+    description: |
+        Minimum transfer speed in mbits/s required to pass the test. 
+        0 disables.
+    type: int
 ```
 
 e.g.
 
-juju set magpie dns_server=8.8.8.8
+juju set magpie dns_server=8.8.8.8 required_mtu=9000 min_speed=1000
+
diff --git a/config.yaml b/config.yaml
index d7eb0e3..17006a8 100644
--- a/config.yaml
+++ b/config.yaml
@@ -27,3 +27,11 @@ options:
     default: False
     description: Enable this if you intend to consume this layer - supresses status messages
     type: boolean
+  required_mtu:
+    default: 0
+    description: Desired MTU for all nodes - block if the unit MTU is different (accounting for encapsulation). 0 disables.
+    type: int
+  min_speed:
+    default: 0
+    description: Minimum transfer speed in mbit/s required to pass the test. 0 disables.
+    type: int
diff --git a/lib/charms/layer/magpie_tools.py b/lib/charms/layer/magpie_tools.py
index c05dc80..b8bc904 100644
--- a/lib/charms/layer/magpie_tools.py
+++ b/lib/charms/layer/magpie_tools.py
@@ -1,32 +1,24 @@
 #!/usr/bin/env python
 
 import os
-import sys
-import signal
 import subprocess
 import re
 from charmhelpers.core import hookenv
 from charmhelpers.core.host import get_nic_mtu
 from charmhelpers.fetch import apt_install
-from charms.reactive import set_state, remove_state
-from charms.reactive.bus import get_state
-import threading
-import time
 
-# is there a better way to get these packages into the unit?
-def install_iperf():
-    apt_install("iperf")
 
 class Iperf():
     """
     Install and start a server automatically
     """
     iperf_out = '/home/ubuntu/iperf_output.txt'
-    def __init__(self):
-        pass
-            
+
+    def install_iperf(self):
+        apt_install("iperf")
+
     def listen(self):
-        cmd = "iperf -s -m | tee " + self.iperf_out + " &"
+        cmd = "iperf -s -m -fm | tee " + self.iperf_out + " &"
         os.system(cmd)
 
     def mtu(self):
@@ -34,35 +26,39 @@ class Iperf():
             for line in f.readlines():
                 if "MTU" in line:
                     match = line
-        return match.split('MTU', 4)[1].split(' ')[1]    
+        try:
+            return match.split('MTU', 4)[1].split(' ')[1]
+        except UnboundLocalError:
+            return "no iperf test results: failed"
 
     def speed(self):
         with open(self.iperf_out) as f:
             for line in f.readlines():
                 if "bits" in line:
                     match = line
-        return match.rsplit(' ', 2)[1]
+        try:
+            return match.rsplit(' ', 2)[1]
+        except UnboundLocalError:
+            return "no iperf test results: failed"
 
-    def stop_server(self):
-        return
+    def selfcheck(self):
+        subprocess.check_output(["iperf", "-c", "localhost", "-t", "1"])
 
-def iperf_selfcheck():
-    subprocess.check_output(["iperf", "-c", "localhost", "-t", "1"])
+    def hostcheck(self, nodes):
+        # Wait for other nodes to start their servers...
+        for node in nodes:
+            msg = "checking iperf on {}".format(node[1])
+            hookenv.log(msg)
+            cmd = "iperf -t1 -c {}".format(node[1])
+            os.system(cmd)
 
-def iperf_hostcheck(nodes):
-    # safe_status('active', 'Leader is checking all other hosts...')  
-    # Wait for other nodes to start their servers...
-    for node in nodes:
-        msg = "checking iperf on {}".format(node[1])
-        hookenv.log(msg)
-        cmd = "iperf -t1 -c {}".format(node[1])
-        os.system(cmd)
 
 def safe_status(workload, status):
     cfg = hookenv.config()
     if not cfg.get('supress_status'):
         hookenv.status_set(workload, status)
 
+
 def ping(input, ping_time, ping_tries):
     ping_string = "ping -c {} -w {} {} > /dev/null 2>&1"\
         .format(ping_tries, ping_time, input)
@@ -90,36 +86,80 @@ def check_local_hostname():
     return result, stderr
 
 
+def check_local_mtu(required_mtu, iface_mtu):
+    if required_mtu == 0:
+        return 0 
+    elif 0 <= (int(iface_mtu) - int(required_mtu)) <= 12:
+        return 100 
+    else:
+        return 200 
+
+
+def check_min_speed(min_speed, iperf_speed):
+    if min_speed == 0:
+        return 0
+    elif min_speed <= iperf_speed:
+        return 100
+    elif min_speed > iperf_speed:
+        return 200
+
+
 def check_nodes(nodes, iperf_client=False):
+    cfg = hookenv.config()
     local_ip = hookenv.unit_private_ip()
     ip_prefix = '.'.join(local_ip.split('.')[0:3])
     iface_line = subprocess.check_output(["ip", "route", "get", ip_prefix])
     primary_iface = str(iface_line).split('dev')[1].split(' ')[1]
     iface_mtu = get_nic_mtu(primary_iface)
+    required_mtu = cfg.get('required_mtu')
+    min_speed = cfg.get('min_speed')
     msg = "MTU for iface: {} is {}".format(primary_iface, iface_mtu)
     hookenv.log(msg, 'INFO')
+    #if required_mtu != 0 and not 0 <= (int(iface_mtu) - int(required_mtu)) <= 12:
+    #    iperf_status = ", local mtu check failed, required_mtu: {}, iface mtu: {}".format(required_mtu, iface_mtu)
+    #elif required_mtu == 0 or 0 <= (int(iface_mtu) - int(required_mtu)) <= 12:
     if not iperf_client:
         iperf = Iperf()
         mtu = iperf.mtu()
         speed = iperf.speed()
-        if iface_mtu == mtu:
-            iperf_status = ", mtu: {}, {} mbit/s".format(mtu, speed)
+        # Make space for 8 or 12 byte variable overhead (TCP options)
+        if "failed" not in mtu:
+            if 0 <= (int(iface_mtu) - int(mtu)) <= 12:
+                iperf_status = ", net mtu ok: {}".format(iface_mtu)
+            else:
+                iperf_status = ", net mtu failed, mismatch: {} packet vs {} on iface {}".format(
+                    mtu, iface_mtu, primary_iface)
         else:
-            iperf_status = ", mtu mismatch: {} packet vs {} on iface {}, {} mbits/s".format(mtu, iface_mtu, primary_iface, speed)
+            iperf_status = ", network mtu check failed"
+        if "failed" not in speed:
+            if check_min_speed(min_speed, int(speed)) == 0:
+                iperf_status = iperf_status + ", {} mbit/s".format(speed)
+            if check_min_speed(min_speed, int(speed)) == 100:
+                iperf_status = iperf_status + ", speed ok: {} mbit/s".format(speed)
+            if check_min_speed(min_speed, int(speed)) == 200:
+                iperf_status = iperf_status + ", speed failed: {} < {} mbit/s".format(speed, str(min_speed))
+        else:
+            iperf_status = iperf_status + ", iperf speed check failed"
     elif iperf_client:
         iperf_status = ", iperf leader, mtu: {}".format(iface_mtu)
-        iperf_hostcheck(nodes)
+        iperf = Iperf()
+        iperf.hostcheck(nodes)
+    if check_local_mtu(required_mtu, iface_mtu) == 100:
+        iperf_status = iperf_status + ", local mtu ok, required: {}".format(required_mtu)
+    elif check_local_mtu(required_mtu, iface_mtu) == 200:
+        iperf_status = iperf_status + ", local mtu failed, required: {}, iface: {}".format(required_mtu, iface_mtu)
     hookenv.log('doing other things after iperf', 'INFO')
-    cfg = hookenv.config()
     cfg_check_local_hostname = cfg.get('check_local_hostname')
     if cfg_check_local_hostname:
         no_hostname = check_local_hostname()
         if no_hostname[0] == '':
             no_hostname = ', local hostname ok'
-            hookenv.log('Local hostname lookup OK: {}'.format(str(no_hostname)), 'INFO')
+            hookenv.log('Local hostname lookup OK: {}'.format(
+                str(no_hostname)), 'INFO')
         else:
             no_hostname = ', local hostname failed'
-            hookenv.log('Local hostname lookup FAILED: {}'.format(str(no_hostname)), 'ERROR')
+            hookenv.log('Local hostname lookup FAILED: {}'.format(
+                str(no_hostname)), 'ERROR')
 
     no_ping = check_ping(nodes)
     no_dns = check_dns(nodes)
@@ -157,9 +197,11 @@ def check_nodes(nodes, iperf_client=False):
             .format(dns_status, str(no_rev), str(no_fwd))
 
     if cfg_check_local_hostname:
-        check_status = '{}{}{}{}'.format(no_ping, str(no_hostname), str(dns_status), str(iperf_status)) 
+        check_status = '{}{}{}{}'.format(no_ping, str(
+            no_hostname), str(dns_status), str(iperf_status))
     else:
-        check_status = '{}{}{}'.format(no_ping, str(dns_status), str(iperf_status))
+        check_status = '{}{}{}'.format(
+            no_ping, str(dns_status), str(iperf_status))
 
     if 'failed' in check_status:
         workload = 'blocked'
diff --git a/metadata.yaml b/metadata.yaml
index 7568b25..8bf6b16 100644
--- a/metadata.yaml
+++ b/metadata.yaml
@@ -2,14 +2,15 @@ name: magpie
 summary: Magpie layer to test networking - ICMP and DNS
 maintainer: Andrew McLeod <andrew.mcleod@canonical.com>
 description: |
-        Magpie will check ICMP and DNS between itself and any
-        peer units deployed - deploy more than one magpie unit
-        for meaningful results.
+        Magpie will check ICMP, DNS, MTU and rx/tx speed between itself and any
+        peer units deployed - deploy more than one magpie unit for meaningful results.
 tags: ["testing", "CI"]
 peers:
   magpie:
     interface: magpie
 series:
+  - artful
+  - zesty
   - xenial
   - trusty
   - precise
diff --git a/reactive/magpie.py b/reactive/magpie.py
index 17e8829..eb5e3b7 100644
--- a/reactive/magpie.py
+++ b/reactive/magpie.py
@@ -1,10 +1,8 @@
 # pylint: disable=unused-argument
 from charms.reactive import when, when_not, set_state, remove_state
-from charms.reactive.bus import get_state
 from charmhelpers.core import hookenv
-from charms.layer.magpie_tools import check_nodes, safe_status, Iperf, install_iperf
-from charmhelpers.core.unitdata import Storage
-import threading
+from charms.layer.magpie_tools import check_nodes, safe_status, Iperf
+
 
 def _set_states(check_result):
     if 'fail' in check_result['icmp']:
@@ -16,15 +14,19 @@ def _set_states(check_result):
     else:
         remove_state('magpie-dns.failed')
 
+
 @when_not('iperf.installed')
 def install_iperf_pkg():
-    install_iperf()
+    iperf = Iperf()
+    iperf.install_iperf()
     set_state('iperf.installed')
 
+
 @when_not('magpie.joined')
 def no_peers():
     safe_status('waiting', 'Waiting for peers...')
 
+
 @when('magpie.joined')
 @when_not('leadership.is_leader', 'iperf.checked')
 def check_check_state(magpie):
@@ -35,6 +37,7 @@ def check_check_state(magpie):
             (hookenv.local_unit() in magpie.get_iperf_checked()):
         set_state('iperf.checked')
 
+
 @when('magpie.joined', 'leadership.is_leader')
 @when_not('iperf.servers.ready')
 def leader_wait_servers_ready(magpie):
@@ -48,18 +51,19 @@ def leader_wait_servers_ready(magpie):
     else:
         remove_state('iperf.servers.ready')
 
+
 @when('magpie.joined')
 @when_not('leadership.is_leader', 'iperf.listening')
 def listen_for_checks(magpie):
     '''
     If im not the leader, and im not listening, then listen
     '''
-    nodes = magpie.get_nodes()
     iperf = Iperf()
     iperf.listen()
     magpie.set_iperf_server_ready()
     set_state('iperf.listening')
 
+
 @when('iperf.servers.ready', 'magpie.joined', 'leadership.is_leader')
 def client_check_hosts(magpie):
     '''
@@ -69,6 +73,7 @@ def client_check_hosts(magpie):
     _set_states(check_nodes(nodes, iperf_client=True))
     magpie.set_iperf_checked()
 
+
 @when('magpie.joined', 'iperf.checked')
 @when_not('leadership.is_leader')
 def check_all_node(magpie):
@@ -77,4 +82,3 @@ def check_all_node(magpie):
     '''
     nodes = magpie.get_nodes()
     _set_states(check_nodes(nodes))
-