View source for Obsolete:Neutron/FakeVM

== Overview ==

FakeVM provides testing environment for Neutron without Nova(excpet nova libvirt vif driver).<br />
With this, we can emulate create/delete/migrate VM port, and operate on the network device like ping.<br />
In addition to the above, FakeVM can emulate multi-compute node with single host.<br />
(However migrate isn't emulated due to interface name conflict)


== Setup ==

Setup Neutron (and its agents) as usual. And run neutron-fakevm-agent.


== Command ==

'''neutron-fakevm <command> [options] [parameters]'''

=== options ===

'''--host <hostname>''': host name to operate

=== command ===

'''create-port <network-id> <instance-id>'''<br />
create Neutron port and plug vif on specified host

'''delete-port <vif-uuid>'''<br />
unplug vif and delete Neutron port

'''migrate <destination-host> <vif-uuid>'''<br />
migrate vif from host that was specified by --host option to destination host

'''plug <vif-uuid>'''<br />
plug vif on specified host

'''unplug <vif-uuid>'''<br />
unplug vif on specified host

'''unplug-all-host <vif-uuid>'''<br />
unplug vif on all host

'''exec <vif-uuid> commands'''<br />
execute commands for <vif-uuid>

== Configuration ==

neutron-fakevm-agent has some configuration parameters.<br />
These parameters belong to [fakevm] group.

=== common parameters ===

'''host = <host name>'''<br />
The name of a host which run the agent.

'''fakevm_agent_plugin = <plugin module>'''<br />
FakeVM Agent Plugin class which is corresponding to Neutron Plugin.<br />
There are three plugins.

linuxbridge Plugin: neutron.debug.fakevm.plugins.linuxbridge.NeutronFakeVMAgentLB

Open vSwitch Plugin: neutron.debug.fakevm.plugins.openvswitch.NeutronFakeVMAgentOVS

Ryu Plugin: neutron.debug.fakevm.plugins.ryu.NeutronFakeVMAgentRyu

'''vif_wrapper = <path>'''<br />
Path to FakeVM VIF Wrapper.<br />
For example, '/opt/stack/neutron/neutron/debug/fakevm/vif.py' for devstack environment.
        
'''nova_conf = <path>'''<br />
Path to nova.conf. This is used by the vif wrapper of FakeVM.<br />
Default is /etc/nova/nova.conf.

The following parameters are used.<br />
libvirt_vif_driver = <vif driver><br />
libvirt_type = <kvm|qemu><br />
libvirt_use_virtio_for_bridges = <True|False><br />
firewall_driver = <firewall driver>

'''enable_multi_node_emulate = <True|False>'''<br />
Enable the multi node emulation. Default is False.

=== For OVS and Ryu plugin ===

'''vir_bridge = <name>'''<br />
Bridge name to be used for the vlan mode of the multi node emulation.

'''use_tunnel = <True|False>'''<br />
Use tunnel or not. set True when tunneling of Neutron OVS plugin is enabled. Default is False.

=== OVS plugin only ===

'''tunnel_interface = <name>'''<br />
Tunnel interface to use when use_tunnel is enabled.


== Limitations ==

=== emulate live-migrate ===

In order to emulate live-migrate, two hosts are necessary.
This is due to conflict of network interface name.
On Linux network interface name is limited to 14 bytes or so.

=== emulate multi-compute node ===

* linuxbridge
At this moment, FakeVM linuxbridge plugin does not support the multi node emulation. This is due to conflict of a bridge name.

* Open vSwitch and Ryu 
At this moment, It is necessary to modify Open vSwitch to use the tunnel mode of the multi node emulation.<br />
See the following URL for the details:<br />
http://openvswitch.org/pipermail/dev/2013-June/028943.html


== Structure ==

In FakeVM agent, there are two functions. One is create of a probe interface.
And the second is emulate the environment of a multiple compute node on the
host. The realization ways are different by each FakeVM agent plugin.

=== Probe interface ===

* Open vSwitch/Ryu

The nova vif driver makes a veth and linux bridge for the port. An interface
of veth is connected to br-int and the other interface is connected to the
linux bridge.
FakeVM agent plugin makes a extra veth and connect an interface to the bridge
and the other interface is used as a probe interface. The agent plugin creates
also a namespace for the probe interface to separate each probes.

    +----------+
    |          |
    |  br-int  |
    |          |
    +---[qvo]--+
          |               .... ns = fakevm-<HOST>-<PORT-ID> ...
          |               :
  +-----[qvb]------+      :
  |                |      :
  |  qbr<PORT-ID> [qfb]-----[qfv]
  |                |      :
  +----------------+      :
                          :

* linuxbridge

Neutron linuxbridge plugin agent handles the interface of the name that
starts with 'tap'. Therefore it is necessary for the name of the probe
interface to starts with 'tap'.
FakeVM agent plugin makes a veth with the interface of the name that starts
with 'tap'. The interface is connected to the bridge for a Neutron network.
And the other is used as a probe interface.

                            .... ns = fakevm-<HOST>-<PORT-ID> ...
  +-------------------+     :
  |                   |     :
  |  brq<NETWORK-ID> [tap]-----[qfv]
  |                   |     :
  +-------------------+     :

=== Multi node emulation ===

* Open vSwitch

There are two modes of VLAN and Tunnel. In VLAN mode, OVS bridge of the each
host is connected via bridge. When a provider network is used, a Linux
bridge is created for each physical network.

  +-------------------+  +-------------------+
  |                   |  |                   |
  |      br-int1      |  |      br-int2      |
  |                   |  |                   |
  +--[int-<PHY-BR1>]--+  +--[int-<PHY-BR2>]--+
            |                      |
            |                      |
  +--[phy-<PHY-BR1>]--+  +--[phy-<PHY-BR2>]--+
  |                   |  |                   |
  |      PHY-BR1      |  |      PHY-BR2      |
  |                   |  |                   |
  +--[qfo<PHY-BR1>]---+  +---[qfo<PHY-BR2>]--+
             |                    |
             |                    |
     +--[qfb<PHY-BR1>]----[qfb<PHY-BR2>]--+
     |                                    |
     |           bfv-<PHY-NET1>           |
     |                                    |
     +------------------------------------+

br-int1 is for a host 1, and br-int2 is for the other host 2.<br />
On host1, bridge_mappings is configured as <PHY-NET1>:<PHY-BR1>.<br />
On host2, bridge_mappings is configured as <PHY-NET1>:<PHY-BR2>.<br />

In the tunnel mode, the dummy interface for each host is created, and an IP
address for tunnel is assigned to the interface.

NOTE: To use tunnel mode, it is necessary to modify Open vSwitch. Please see Limitations section above.

* linuxbridge

FakeVM agent linuxbridge plugin does not support the multi node emulation
now. Because the name of the bridge which Neutron linuxbridge plugin makes
conflicts. The name of the bridge is made by prefix 'brq' and network ID.
The prefix is defined statically, and the network ID is unique. So we cannot
avoid conflict.

* Ryu

There are two modes like OVS. VLAN mode is simpler than OVS's because Neutron
Ryu plugin does not support the provider network yet. It connects each OVS
bridge by a bridge simply.

  +-------------------+  +-------------------+
  |                   |  |                   |
  |      br-int1      |  |      br-int2      |
  |                   |  |                   |
  +----[qfo<HOST1>]---+  +---[qfo<HOST2>]----+
            |                      |
            |                      |
     +--[qfb<HOST1>]--------[qfb<HOST2>]--+
     |                                    |
     |             br-fakevm              |
     |                                    |
     +------------------------------------+

The tunnel mode is same as OVS's.


== Example ==

=== Single node, create a port and do ping from the probe ===

Use devstack to setup.

localrc

    # only runs keystone and neutron. other components are not necessary
    ENABLED_SERVICES=""  # disable all of default enabled services
    enable_service rabbit
    enable_service key
    enable_service mysql
    enable_service neutron
    enable_service q-agt
    enable_service q-l3
    enable_service q-dhcp
    enable_service q-svc
    # q-meta makes sense only with nova
    # plus your neutron plugin settings...
    
    Q_PLUGIN=openvswitch
    ENABLE_TENANT_TUNNELS=False
    ENABLE_TENANT_VLANS=True
    PHYSICAL_NETWORK=phy1
    TENANT_VLAN_RANGE=200:300
    OVS_PHYSICAL_BRIDGE=br-eth1
    
    # And necessary parameters...

Run devstack, then start fakevm agent.

fakevm.ini

    [default]
    debug = True
    verbose = True
    
    [fakevm]
    host = guest1
    vif_wrapper = /opt/stack/neutron/neutron/debug/fakevm/vif.py
    nova_conf = /etc/nova/nova.conf
    fakevm_agent_plugin = neutron.debug.fakevm.fakevm_agent_ovs.NeutronFakeVMAgentOVS
    enable_multi_node_emulate = False

  $ neutron-fakevm-agent --config-file /etc/neutron/neutron.conf \
  --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini \
  --config-file ./fakevm.ini

Then create a port.

  $ . ./openrc admin demo
  $ neutron net-list
  +--------------------------------------+---------+-------------------------------------------------------+
  | id                                   | name    | subnets                                               |
  +--------------------------------------+---------+-------------------------------------------------------+
  | 18f725c7-dd56-42ba-975d-e444152a0377 | public  | 76d5e916-2353-4025-a61a-2e5ca8a15708 192.168.100.0/24 |
  | 5379c0d2-9a0d-4bc5-a028-a0c0c7df336d | private | ee138a17-cdf4-436f-b651-0245201ea71e 10.0.0.0/24      |
  +--------------------------------------+---------+-------------------------------------------------------+
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  create-port --host guest1 5379c0d2-9a0d-4bc5-a028-a0c0c7df336d i-xxxx
  :::
  VM port created on guest1: vif_uuid: d7e577a9-a9cd-46a4-870c-2754641e6b87 mac: fa:16:3e:87:e6:4f tenant_id: 43dd8e1496104939bca6256edf874661
  fixed_ips: [{u'subnet_id': u'ee138a17-cdf4-436f-b651-0245201ea71e', u'ip_address': u'10.0.0.3'}]
  netowrk: {u'status': u'ACTIVE', u'subnets': [u'ee138a17-cdf4-436f-b651-0245201ea71e'], u'name': u'private', u'provider:physical_network': u'phy1', u'admin_state_up': True, u'tenant_id': u'43dd8e1496104939bca6256edf874661', u'provider:network_type': u'vlan', u'router:external': False, u'shared': False, u'id': u'5379c0d2-9a0d-4bc5-a028-a0c0c7df336d', u'provider:segmentation_id': 200}
  $ 
  $ neutron port-list
  +--------------------------------------+------+-------------------+--------------------------------------------------------------------------------------+
  | id                                   | name | mac_address       | fixed_ips                                                                            |
  +--------------------------------------+------+-------------------+--------------------------------------------------------------------------------------+
  | 4c12d56c-83fd-4b8e-8ad9-7b5823259e7d |      | fa:16:3e:07:5e:3e | {"subnet_id": "ee138a17-cdf4-436f-b651-0245201ea71e", "ip_address": "10.0.0.2"}      |
  | 9ffdbffd-e8eb-4ae2-ad86-d0ca50303251 |      | fa:16:3e:34:55:5e | {"subnet_id": "76d5e916-2353-4025-a61a-2e5ca8a15708", "ip_address": "192.168.100.2"} |
  | b167fd32-3d4d-4a21-911e-230aa245bf32 |      | fa:16:3e:bb:91:68 | {"subnet_id": "ee138a17-cdf4-436f-b651-0245201ea71e", "ip_address": "10.0.0.1"}      |
  | d7e577a9-a9cd-46a4-870c-2754641e6b87 |      | fa:16:3e:87:e6:4f | {"subnet_id": "ee138a17-cdf4-436f-b651-0245201ea71e", "ip_address": "10.0.0.3"}      |
  +--------------------------------------+------+-------------------+--------------------------------------------------------------------------------------+
  $ 

Assign IP address to the probe interface by using dhclient.

  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest1 d7e577a9-a9cd-46a4-870c-2754641e6b87 "ip link"
  :::
  VM port executeon guest1: d7e577a9-a9cd-46a4-870c-2754641e6b87 ip link
  19: qfvd7e577a9-a: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
      link/ether fa:16:3e:87:e6:4f brd ff:ff:ff:ff:ff:ff
  21: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
      link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest1 d7e577a9-a9cd-46a4-870c-2754641e6b87 "dhclient -4 -v qfvd7e577a9-a"
  :::
  VM port executeon guest1: d7e577a9-a9cd-46a4-870c-2754641e6b87 dhclient -4 -v qfvd7e577a9-a
  
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest1 d7e577a9-a9cd-46a4-870c-2754641e6b87 "ifconfig"
  :::
  VM port executeon guest1: d7e577a9-a9cd-46a4-870c-2754641e6b87 ifconfig
  lo        Link encap:Local Loopback  
            inet addr:127.0.0.1  Mask:255.0.0.0
            inet6 addr: ::1/128 Scope:Host
            UP LOOPBACK RUNNING  MTU:16436  Metric:1
            RX packets:0 errors:0 dropped:0 overruns:0 frame:0
            TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:0 
            RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
  
  qfvd7e577a9-a Link encap:Ethernet  HWaddr fa:16:3e:87:e6:4f  
            inet addr:10.0.0.3  Bcast:10.0.0.255  Mask:255.255.255.0
            inet6 addr: fe80::f816:3eff:fe87:e64f/64 Scope:Link
            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
            RX packets:20 errors:0 dropped:0 overruns:0 frame:0
            TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:1000 
            RX bytes:2304 (2.3 KB)  TX bytes:1528 (1.5 KB)

Ping from the probe interface to the DHCP port on Neutron network.

  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest1 d7e577a9-a9cd-46a4-870c-2754641e6b87 "ping -c1 10.0.0.2"
  :::
  VM port executeon guest1: d7e577a9-a9cd-46a4-870c-2754641e6b87 ping -c1 10.0.0.2
  
  PING 10.0.0.2 (10.0.0.2) 56(84) bytes of data.
  64 bytes from 10.0.0.2: icmp_req=1 ttl=64 time=44.1 ms
  
  --- 10.0.0.2 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 44.159/44.159/44.159/0.000 ms
  
  $ 

=== Multi node and emulate live-migration ===

On the other physical host, run FakeVM agent and Neutron plugin agent.

fakevm.ini

    [default]
    debug = True
    verbose = True
    
    [fakevm]
    host = guest2
    vif_wrapper = /opt/stack/neutron/neutron/debug/fakevm/vif.py
    nova_conf = /etc/nova/nova.conf
    fakevm_agent_plugin = neutron.debug.fakevm.fakevm_agent_ovs.NeutronFakeVMAgentOVS
    enable_multi_node_emulate = False

  $ neutron-fakevm-agent --config-file /etc/neutron/neutron.conf \
  --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini \
  --config-file ./fakevm.ini

  $ sudo ovs-vsctl add-br br-int
  $ sudo ovs-vsctl add-br br-eth1
  $ sudo ovs-vsctl add-port br-eth1 eth1
  $ neutron-openvswitch-agent --debug --verbose \
  --config-file /etc/neutron/neutron.conf \
  --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini

Then operate on the original node.

  $ sudo ovs-vsctl add-port br-eth1 eth1
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  create-port --host guest2 5379c0d2-9a0d-4bc5-a028-a0c0c7df336d i-yyyy
  :::
  VM port created on guest2: vif_uuid: 418874ff-571b-46e2-a28a-75fe8afcb9e1 mac: fa:16:3e:c8:c0:34 tenant_id: 43dd8e1496104939bca6256edf874661
  fixed_ips: [{u'subnet_id': u'ee138a17-cdf4-436f-b651-0245201ea71e', u'ip_address': u'10.0.0.4'}]
  netowrk: {u'status': u'ACTIVE', u'subnets': [u'ee138a17-cdf4-436f-b651-0245201ea71e'], u'name': u'private', u'provider:physical_network': u'phy1', u'admin_state_up': True, u'tenant_id': u'43dd8e1496104939bca6256edf874661', u'provider:network_type': u'vlan', u'router:external': False, u'shared': False, u'id': u'5379c0d2-9a0d-4bc5-a028-a0c0c7df336d', u'provider:segmentation_id': 200}
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest2 418874ff-571b-46e2-a28a-75fe8afcb9e1 "ip link"
  :::
  VM port executeon guest2: 418874ff-571b-46e2-a28a-75fe8afcb9e1 ip link
  17: qfv418874ff-5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
      link/ether fa:16:3e:c8:c0:34 brd ff:ff:ff:ff:ff:ff
  19: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
      link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest2 418874ff-571b-46e2-a28a-75fe8afcb9e1 "dhclient -4 -v qfv418874ff-5"
  :::
  VM port executeon guest2: 418874ff-571b-46e2-a28a-75fe8afcb9e1 dhclient -4 -v qfv418874ff-5
  
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest2 418874ff-571b-46e2-a28a-75fe8afcb9e1 "ifconfig"
  :::
  VM port executeon guest2: 418874ff-571b-46e2-a28a-75fe8afcb9e1 ifconfig
  lo        Link encap:Local Loopback  
            inet addr:127.0.0.1  Mask:255.0.0.0
            inet6 addr: ::1/128 Scope:Host
            UP LOOPBACK RUNNING  MTU:16436  Metric:1
            RX packets:0 errors:0 dropped:0 overruns:0 frame:0
            TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:0 
            RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
  
  qfv418874ff-5 Link encap:Ethernet  HWaddr fa:16:3e:c8:c0:34  
            inet addr:10.0.0.4  Bcast:10.0.0.255  Mask:255.255.255.0
            inet6 addr: fe80::f816:3eff:fec8:c034/64 Scope:Link
            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
            RX packets:22 errors:0 dropped:0 overruns:0 frame:0
            TX packets:15 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:1000 
            RX bytes:2130 (2.1 KB)  TX bytes:2734 (2.7 KB)
  
  
  $ 

Ping from the other node to the original node.

  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest2 418874ff-571b-46e2-a28a-75fe8afcb9e1 "ping -c1 10.0.0.3"
  :::
  VM port executeon guest2: 418874ff-571b-46e2-a28a-75fe8afcb9e1 ping -c1 10.0.0.3
  
  PING 10.0.0.3 (10.0.0.3) 56(84) bytes of data.
  64 bytes from 10.0.0.3: icmp_req=1 ttl=64 time=10.9 ms
  
  --- 10.0.0.3 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 10.921/10.921/10.921/0.000 ms
  
  $ 

Then try emulation of live-migration

  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest2 418874ff-571b-46e2-a28a-75fe8afcb9e1 "dhclient -4 -r qfv418874ff-5"
  :::
  VM port executeon guest2: 418874ff-571b-46e2-a28a-75fe8afcb9e1 dhclient -4 -r qfv418874ff-5
  
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  migrate --host guest2 guest1 418874ff-571b-46e2-a28a-75fe8afcb9e1
  :::
  VM migrate : 418874ff-571b-46e2-a28a-75fe8afcb9e1 guest2 -> guest1
  $ 
  $ ip link|grep qvo
  17: qvod7e577a9-a9: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
  32: qvo418874ff-57: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
  $ 

=== Multi node emulation ===

On the original host, modify configuration to enable the multi node mode and restart FakeVM agent.

fakevm.ini

    [default]
    debug = True
    verbose = True
    
    [fakevm]
    host = guest1
    vif_wrapper = /opt/stack/neutron/neutron/debug/fakevm/vif.py
    nova_conf = /etc/nova/nova.conf
    fakevm_agent_plugin = neutron.debug.fakevm.fakevm_agent_ovs.NeutronFakeVMAgentOVS
    enable_multi_node_emulate = True
    use_tunnel = False
    vir_bridge = br-fakevm

  $ neutron-fakevm-agent --config-file /etc/neutron/neutron.conf \
  --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini \
  --config-file ./fakevm.ini

Run Neutron plugin agent and FakeVM agent on the same machine with different configuration.

guest3.ini

    [ovs]
    integration_bridge = br-int2
    bridge_mappings = phy1:br-eth2
    
    [fakevm]
    host = guest3

  $ neutron-fakevm-agent --config-file /etc/neutron/neutron.conf \
  --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini \
  --config-file ./fakevm.ini --config-file ./guest3.ini

  $ neutron-openvswitch-agent --debug --verbose \
  --config-file /etc/neutron/neutron.conf \
  --config-file /etc/neutron/plugins/openvswitch/ovs_neutron_plugin.ini \
  --config-file ./guest3.ini

Then create a port on the emulated node.

  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  create-port --host guest3 5379c0d2-9a0d-4bc5-a028-a0c0c7df336d i-zzzz
  :::
  VM port created on guest3: vif_uuid: c29cfc8c-c978-4025-8fa9-0a6c791bb31b mac: fa:16:3e:fc:f8:3e tenant_id: 43dd8e1496104939bca6256edf874661
  fixed_ips: [{u'subnet_id': u'ee138a17-cdf4-436f-b651-0245201ea71e', u'ip_address': u'10.0.0.5'}]
  netowrk: {u'status': u'ACTIVE', u'subnets': [u'ee138a17-cdf4-436f-b651-0245201ea71e'], u'name': u'private', u'provider:physical_network': u'phy1', u'admin_state_up': True, u'tenant_id': u'43dd8e1496104939bca6256edf874661', u'provider:network_type': u'vlan', u'router:external': False, u'shared': False, u'id': u'5379c0d2-9a0d-4bc5-a028-a0c0c7df336d', u'provider:segmentation_id': 200}
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest3 c29cfc8c-c978-4025-8fa9-0a6c791bb31b "ip link"
  :::
  VM port executeon guest3: c29cfc8c-c978-4025-8fa9-0a6c791bb31b ip link
  49: qfvc29cfc8c-c: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
      link/ether fa:16:3e:fc:f8:3e brd ff:ff:ff:ff:ff:ff
  51: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
      link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
  
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest3 c29cfc8c-c978-4025-8fa9-0a6c791bb31b "dhclient -4 -v qfvc29cfc8c-c"
  :::
  VM port executeon guest3: c29cfc8c-c978-4025-8fa9-0a6c791bb31b dhclient -4 -v qfvc29cfc8c-c
  
  $ 
  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest3 c29cfc8c-c978-4025-8fa9-0a6c791bb31b "ifconfig"
  :::
  VM port executeon guest3: c29cfc8c-c978-4025-8fa9-0a6c791bb31b ifconfig
  lo        Link encap:Local Loopback  
            inet addr:127.0.0.1  Mask:255.0.0.0
            inet6 addr: ::1/128 Scope:Host
            UP LOOPBACK RUNNING  MTU:16436  Metric:1
            RX packets:0 errors:0 dropped:0 overruns:0 frame:0
            TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:0 
            RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
  
  qfvc29cfc8c-c Link encap:Ethernet  HWaddr fa:16:3e:fc:f8:3e  
            inet addr:10.0.0.5  Bcast:10.0.0.255  Mask:255.255.255.0
            inet6 addr: fe80::f816:3eff:fefc:f83e/64 Scope:Link
            UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
            RX packets:21 errors:0 dropped:0 overruns:0 frame:0
            TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
            collisions:0 txqueuelen:1000 
            RX bytes:2076 (2.0 KB)  TX bytes:1272 (1.2 KB)
  
  
  $ 

Ping from the emulated node to the original node.

  $ neutron-fakevm --config-file /etc/neutron/neutron.conf \
  exec --host guest3 c29cfc8c-c978-4025-8fa9-0a6c791bb31b "ping -c1 10.0.0.3"
  :::
  VM port executeon guest3: c29cfc8c-c978-4025-8fa9-0a6c791bb31b ping -c1 10.0.0.3
  
  PING 10.0.0.3 (10.0.0.3) 56(84) bytes of data.
  64 bytes from 10.0.0.3: icmp_req=1 ttl=64 time=11.8 ms
  
  --- 10.0.0.3 ping statistics ---
  1 packets transmitted, 1 received, 0% packet loss, time 0ms
  rtt min/avg/max/mdev = 11.899/11.899/11.899/0.000 ms
  
  $