Deep dive into Quantum 1. Quantum is the network connectivity service for OpenStack that provides an API to dynamically request and configure virtual networks. It integrates virtual networks with other OpenStack services. 2. The Open vSwitch plugin uses a quantum agent to poll the local Open vSwitch instance and configure flows to implement the logical network model defined in the central database. 3. Plugins hide the backend network technology and provide a generic tenant API for creating and configuring virtual networks, while agents perform the actual network configuration on each physical host.

1. Deep dive into Quantum
2012/11/10 COSUG Meet up
Luo, Zhongyue
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2. TODO
Intro
Overview
File Structure
Components
REST APIs
Under the hood
– Configuration: Open vSwitch plugin
– How does the plugin get loaded?
– Why is there a agent for the Open vSwitch plugin?
Resources
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3. Intro
What is Quantum?
Network-Connectivity-as-a-Service for OpenStack
Goal
• Provides an API to dynamically request and configure
virtual networks
• Support API and API extensions to provide advanced
network capabilities
• Integrate virtual networks with other OpenStack services
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4. Intro
VM VM VM VM
A1 A2 B1 B2
Tenant View
Network A Network B
Phy Srv 1 Phy Srv 2 Phy Srv 3
VM VM VM VM
A1 B1 A2 B2
Hypervisor Hypervisor Hypervisor
Provider View
Data Centre Network
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5. Intro
VM1 VM2 virtual server
Nova 10.0.0.2 10.0.0.3
virtual interface
3 (VIF)
2 virtual port
Quantum Net1
L2 virtual
10.0.0.0/24
network
1 Subnet
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6. Intro
TenantA-VM1 TenantA-VM2 TenantA-VM3
10.0.0.2 10.0.0.3 9.0.0.3 10.0.1.2
TenantA-VM4 Tenant-A Net1 Tenant-A Net2
172.16.0.30 10.0.0.0/24 10.0.1.0/24
Tenant-A Net3
172.16.0.0/24
Not
VPN necessarily a
VM!
Tenant-A On
Premise Net Public Net
172.16.0.0/24 88.0.0.0/18
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7. File Structure
extensions
choose
one
start
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8. File Structure
agent extension
implementations implementations
handler
setup
api-pate.ini
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9. Components
Plugins
• Cloud Operators weigh trade-offs, choose a plugin
• Hide backend technology
Server
• A generic tenant API to create and configure “virtual
networks”
Agent
• Daemon to perform the actual network configuration on
each physical host
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10. Components
API Extentions
• QoS, SLA, L3 forwarding, Security, Metering, etc.
• Enables innovation in virtual networking.
• Extensions implemented by many plugins can become
“core”.
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11. Overview
RPC
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12. Overview http://wiki.openstack.org/Quantum?action=AttachFil
e&do=get&target=quantum-technical-archicture.ppt
Dhcp agent
quantum-server
get_active_networks
get_network_info
get_dhcp_port
release_dhcp_port
release_port_fixed_ip
update_lease_expiration
Plugin agent Quantum rest api
(resource CUD)
get_device_details
update_device_down network_delete tunnel_update port_update
tunnel_sync
q-agent-notifier- q-agent-notifier- q-agent-notifier-
Exchange: Quantum network-delete_fanout tunnel-update_fanout port-update_fanout
topic fanout fanout fanout
Queue: q-agent-notifier- q-agent-notifier- q-agent-notifier-
q-plugin notifications.info network-delete_fanout tunnel-update_fanout port-update_fanout
_{uuid4} _{uuid4} _{uuid4}
Comsumer: quantum-server Dhcp agent Plugin agent
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13. Rest APIs
Networks
• Represents an L2 network segment
• Can associate with a set of subnets and ports
http://docs.openstack.org/api/openstack-network/1.0/content/Networks.html
quantum/api/v2/attributes.py
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14. Rest APIs
Subnets
• Represents a range of IP addresses
• Allocated to devices
• API request specifications
o quantum/api/v2/attributes.py
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15. Rest APIs
Ports
• A connection point of a device to attach to a L2 Quantum
network
• Allocated to devices
http://docs.openstack.org/api/openstack-network/1.0/content/Ports.html
• API request specifications
o quantum/api/v2/attributes.py
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16. Under the Hood

17. Configuration: Open vSwitch plugin
Install KVM, Open vSwitch and configure your environment
http://blog.scottlowe.org/2012/08/17/installing-kvm-and-open-vswitch-on-ubuntu/
Edit etc/quantum/plugins.ini
core_plugin = quantum.plugins.openvswitch.ovs_quantum_plugin.OVSQuantumPlugin
Edit etc/quantum/plugins/openvswitch/ovs_quantum_plugin.ini
mysql://root:nova@127.0.0.1:3306/ovs_quantum .
NOTE: The database IP address in the file should be reachable by all compute nodes.
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18. Configuration: Open vSwitch plugin
Edit nova.conf on nova-network and nova-manage hosts
network_manager=nova.network.quantum.manager.QuantumManager
linuxnet_interface_driver=nova.network.linux_net.LinuxOVSInterfaceDriver
linuxnet_ovs_integration_bridge=br-int
Edit nova.conf on nova-compute hosts
libvirt_ovs_bridge=br-int
libvirt_vif_type=ethernet
libvirt_vif_driver=nova.virt.libvirt.vif.LibvirtOpenVswitchDriver
Start the agent
$ python ovs_quantum_agent.py ovs_quantum_plugin.ini
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19. How does the plugin get loaded?
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20. How does the plugin get loaded?
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21. How does the plugin get loaded?
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22. How does the plugin get loaded?
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23. How does the plugin get loaded?
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24. How does the plugin get loaded?
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25. How does the plugin get loaded?
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26. Why is there a agent for the Open vSwitch
plugin?
The OVS agent
• Checks the configuration and mappings consistency of the
local Open vSwitch environment and the central mysql
database
• Polls directly to the local Open vSwitch instance
• Configures flows to implement the logical data model.
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27. Why is there a agent for the Open vSwitch
plugin?
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28. Why is there a agent for the Open vSwitch
plugin?
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29. Why is there a agent for the Open vSwitch
plugin?
OVS cli wrappers
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30. Resources
http://github.com/openstack/quantum
http://wiki.openstack.org/Quantum
http://docs.openstack.org/api/openstack-network/1.0/content/
http://docs.openstack.org/trunk/openstack-network/admin/content/index.html
http://openvswitch.org/openstack/documentation/
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