Quantum Folsom Summit Developer Overview

Intro to OpenStack Quantum

Dan Wendlandt – Quantum Hacker & [email protected]

twitter - danwendlandt

mailto:[email protected]

Caveats

• Contents may shift in flight…• Quantum is young: there are lots of things

that it COULD do, but doesn’t yet. • I will not finish these slides…

Outline

• Why Quantum?• What is Quantum? – Basic Concepts & Demo– High-level System Architecture

• Current Project Status• Future Directions• Frequently Asked Questions

Why Quantum?

What is OpenStack?• Open Source Cloud Software…• A collection of “cloud services”• Each service includes: – A tenant-facing API that exposes

logical abstractions for consuming the service.

– One or more backend implementations of that API

In the beginning..

Compute

Storage

Network

Nova

Swift (Objects)

Glance (Images)

?

*-as-a-Service Capability OpenStack Service

Why Quantum?

• Networking was sub-component of Nova• Two Key Problems:

#1: Limited technology “baked in” to design. #2: No tenant control of networking.

Problem #1: Technology Limitations

• Cloud stresses networks like never before: – High-density multi-tenancy, massive scale– Strict uptime requirements.– Integrate with legacy hosting environments /

remote data centers.– Price pressure to use commodity gear. – VM mobility

• Nova provides only basic technologies: – VLANs are only option for multitenancy– Used simple Linux Bridge (no advanced QoS,

ACLs, or monitoring)– “network controller” node is centralized single-

point of failure for large networks.

VLANs are Great!- Stone Age Man

Why Quantum? Reason #1

• New networking technologies are emerging to try and tackle these challenges.– Software-defined Networking (SDN) / OpenFlow– Overlay tunneling: VXLAN, NVGRE, STT– Fabric solutions: FabricPath, Qfabric, etc. – [ insert other solution here ]

• Quantum provides a “plugin” mechanism to enable different technologies implement calls made via the Quantum API.

• Choice is a good thing!

Problem #2: No Tenant Control

“You can have any color as long as its black.“- Henry Ford about the Model-T

• Cloud tenants want to replicate rich enterprise network topologies: – Ability to create “multi-tier” networks

(e.g., web tier, app tier, db tier) – Control over IP addressing. – Ability to insert and configure your own

services (e.g., firewall, IPS)– VPN/Bridge to remote physical hosting

or customer premises. • Nova provides no tenant control:

– No way to control topology.– Cloud assigns IP prefixes + addresses. – No generic service insertion.

Why Quantum? Reason #2

• Base Quantum API lets tenants create multiple private networks, control IP addressing on them.

• Quantum API extensions enable additional control:– Security & Compliance Policies– Quality-of-Service– Monitoring + Troubleshooting

• “Advanced Network Services” such as firewall, intrusion detection, VPN, can be inserted either as VMs that route between networks, or as API extensions.

All is Right with the World…

Compute

Storage

Network

Nova

Swift (Objects)

Glance (Images)

*-as-a-Service Capability OpenStack Service

Quantum

Why Quantum?

Questions?

What is Quantum?

Quantum Basics (by analogy to Nova)Nova Quantum

*-as-a-service Compute Network

Major API abstractions “virtual servers”: represents a host with CPU, memory, disk, and NICs.

“virtual networks”: A basic L2 network segment.“virtual ports”: Attachment point for devices connecting to virtual networks.

Interactions with other OpenStack services.

virtual servers use “virtual images” from Glance.

virtual ports are linked to vNICs on “virtual servers”.

Supports different back-end technologies

“virt-drivers” for KVM, XenServer, Hyper-V, VMWare ESX

“plugins” for Open vSwitch Cisco UCS, Linux Bridge, Nicira NVP, Ryu Controller (and more!).

API Extensibility for new or back-end specific features.

keypairs, instance rescue, volumes, etc.

quality-of-service, port statistics, security groups, etc.

API Abstractions

Net110.0.0.0/24

VM110.0.0.2Nova

Quantum virtual network

VM210.0.0.3

virtual port

virtual server

virtual interface (VIF)

Quantum Rest API Abstraction Details

• Virtual Networks:– Equivalent to a “virtual VLAN”, a dedicated L2 segment. – Example: quantum.foo.com/<tenant-id>/network/<network-id>

• Virtual Ports:– Where a virtual interface (e.g., Nova vNIC) attaches to a network. – Example:

quantum.foo.com/<tenant-id>/network/<network-id>/port/<port-id>

• API Extensions: – Can add properties to existing network/port abstractions (e.g., QoS

settings for a virtual port). – Can introduce new API entities (e.g., Security Groups that are linked to

ports, or L3 + NAT Forwarding Elements that attach to networks).

Old Model: Static Nova Networking

Public Net88.0.0.0/18

• Single network exists (per-project or global). • VMs automatically get a vNIC on that single network on boot. • Tenants have no control over IP addressing.

TenantA-VM188.0.0.2

TenantB-VM188.0.0.3

TenantA-VM288.0.0.4

TenantA-VM388.0.0.5

Quantum Model: Dynamic Network Creation + Association

TenantA-VM110.0.0.2

TenantA-VM39.0.0.2

• Tenant can use API to create many networks.• When booting a VM, define which network(s) it

should connect to.• Can even plug-in instances from other services

(e.g., a load-balancing service).

TenantA-VM210.0.0.3 9.0.0.3

Load Balancer

Public Net88.0.0.0/18

Tenant-A Net110.0.0.0/24

Tenant-A Net29.0.0.0/24

• “Plugin” model give cloud operators choices: – Advanced Features (exposed as API extensions)– Cost– Scale – High Availability – Hypervisor + Network HW Compatibility – Manageability / Polish

• Abstract logical API – tenants don’t see underlying technologies– Example: VLANs vs. tunneling

Quantum Architecture Basics

A bit about plugins (more later!)

• A common point of confusion. • Define “quantum plugin”:

Code that communicates with network devices to implement a particular set of Quantum API calls.

• API currently has one set of calls for “base L2” networking => one plugin running at a time.

• A plugin is not a “driver”. A single plugin can talk to different types of network devices.

Nova ComputeNova Compute


Quantum Architecture (simple)

Tenant Scripts

Horizon

Nova

API Clients Quantum Server

Quantum Plugin

Create-net...

Create-port

virtual switch

Internal plugin communication.Quantum

API

Create-net...

Create-port

Interfaces from a service like Nova plug into a

switch manages by the Quantum plugin.

API + Plugin = Quantum Service

Uniform API for all clients

API Extensions DB



Quantum Architecture (advanced)

Tenant Scripts

Horizon

Nova

API Clients Quantum Server

Quantum Plugin

Create-net...

Create-port

virtual switch

Internal plugin communication.

Quantum API

Create-net...

Create-port

Interfaces from a service like Nova plug into a

switch manages by the Quantum plugin.

API + Plugin = Quantum Service

Uniform API for all clients

External Manager

DB

DBAPI

Extensions

Current Project Status

Project Status: Essex Cycle• Started at Diablo summit, “incubated” for Essex, “core” in Folsom. • Available at: http://launchpad.net/quantum• Docs at: http://docs.openstack.org/incubation/• Current Capabilities:

– v1.1 of the Quantum L2 API, with extension support. – API client library and CLI – Nova Integration via the QuantumManager– Plugin framework & several publicly available plugins:

• Open vSwitch Plugin• Cisco UCS/Nexus Plugin • Linux Bridge Plugin• Nicira Network Virtualization Platform (NVP)• Ryu OpenFlow Controller

– Integrated with “devstack” (see: http://wiki.openstack.org/QuantumDevstack)– Packaging for Ubuntu 12.04 / Fedora 17 / Debian .

Project Status: Two Deployment Models

• Proxied Quantum (available now): – QuantumManager in Nova is only Quantum API client. – Cloud admin must define networks with nova-manage. – Tenant can place VMs on different networks using nova extension (--nic

option in nova client).– Allows cloud provider to leverage advanced networking technologies, but

doesn’t give tenant’s network control. • Direct Quantum (Folsom Target):

– Tenants can create their own networks, determine their own IP addressing via Quantum API.

– Tenants can insert other logical services exposed by service provider (e.g., router, VPN) using extensions.

– Requires Keystone Authn/Authz for API and a tenant API for IPAM (i.e., Melange)

Project Status: Who should use Quantum?

• “Early adopters” already putting Quantum into trial & production OpenStack deployments.

• Caution: Deployments are by people at the cutting edge, require significant familiarity with Quantum.

• Folsom release will be first target for widespread adoption.

Project status: Try it Yourself

• Now integrated with DevStack• http://wiki.openstack.org/QuantumDevstack• Use nova-manage to create networks (i.e.

proxied mode)• Spin up VMs with -- nic option. • See Quantum Administrator Guide for details– http://docs.openstack.org/incubation/openstack-

network/admin/content/

http://wiki.openstack.org/QuantumDevstack

Folsom Priorities #1

• Enable tenant control of networking– Keystone Authn, Authz– Expose IPAM to tenants (e.g., integrate Melange)– Rework Nova integration (remove ties to Nova DB)– Horizon integration, CLI rewrite.


• Improve system quality + scale– Unit test– System-test– CI-integration– API scaling


• Move networking from Nova to Quantum– L3 Forwarding + NAT/Floating IPs– Security Groups– DHCP injection– VPN (?)

• Follow Quantum pattern:– Enable tenant control by extending existing API– Allow pluggable backends

Developer, Developer Developers• Folsom goals, including becoming

default network platform, are VERY ambitious

• We’ll need many more developers to:– Implement new functionality

(particularly for open source plugins!)– Be familiar enough with Quantum to

answer user questions on ML, launchpad, IRC, etc.

• Let’s help grow the team.

Deeper Technical Dive(until we run out of time)

Basic code flow

“Create Network” in Proxied Mode

• Network created by cloud operator using nova-manage:

• QuantumManager (QM) in Nova calls to Quantum, creates network.

• QM creates IPAM subnet using Nova DB or Melange.

• QM stashes resulting data in Nova DB.

“Create VM” in Proxied Mode• Tenant uses Nova API to create VM• Extension allows VM to pass in a list of network UUIDs

(see --nic option in novaclient)• Nova-compute makes nova RPC call to

“allocate_for_instance” method of network manager. • QM creates a VIF entry in nova DB for each attached

network. • QM creates a Quantum port for each VIF, tells Quantum

the associated “vif-id”. • Nova-compute creates VM, and “vif-plugging” reports

bindings between “vif-id” and “switch port” to Quantum plugin.

“Create Network” in Direct Mode

• Tenant contacts Quantum directly, passing in network details, including associated IPAM subnet.

• All data is stored in Quantum plugin (nothing stored in Nova).

“Create VM” in Proxied Mode• Tenant uses Nova API to create VM• Extension allows VM to pass in a list of

network UUIDs (see --nic option in novaclient)• Nova-compute makes direct REST call to

Quantum, creating a port for each network (no more QM or nova-network)

• Nova-compute creates VM, and “vif-plugging” reports bindings between “quantum port” and “switch port” to Quantum plugin.

same

Plugin Details

Simple VLAN Plugin Example

• Plugin assumes all VLANs are trunked to all hypervisors (similar to nova-network)

• When new q-network is created, creates a DB entry mapping network to a free VLAN.

• Stores port + attachment mappings in DB. • Runs agent on hypervisor to recognize new vswitch

ports that represent Nova interfaces. • When new vswitch port appears, agent finds q-

port + q-network associated with interface-id, configures vswitch port with correct VLAN.

Persistent Data Stored by Plugins

• All persistent data (networks, ports, etc) is stored by the plugin, not the API layer.

• Why?– Data schema for plugin depends on plugin-specific

implementation details (e.g, networks -> VLANs)– Data schema depends on supported extensions.– Plugins may make different trade-offs around scale, HA,

data consistency, etc. • Common data models are shared across plugins

using a library of “base” SQLAlchemy models.

Why separate plugins + drivers?

• Plugins may make decisions that are technology, but not device-specific (e.g., mapping q-network ‘foo’ to VLAN 99).

• That decision must be made by only a single entity… if multiple such decisions were made by different plugins, they likely would conflict.

• The plugin may use drivers to communicate the results of this decision to different devices (e.g., it may configure the VLAN on a vswitch port, and tell the upstream physical switch to trunk that VLAN).

• Driver code can be shared across plugins with libraries.

Frequently Asked Questions

• Is OpenFlow required for Quantum– A: Nope! OpenFlow is just one technology that

Quantum enables.• Is Quantum “software-defined networking”?– It depends…

• How does Quantum compare to Amazon VPC? – A: Have similar goal of enabling advanced

networking in cloud. Quantum will give cloud operators ability to compete with (and go beyond) VPC feature-set.

Bonus Slides

Basic Quantum + Nova API FlowAPI Client Quantum Server

Create Network (POST /tenant1/network)

Network UUID: ‘abc’

Create Server (POST /tenant1/server)

Nova Server

Server UUID: ‘def’

Get Server Interface(s) (GET /tenant1/server/def/interface)

Server Interface UUID List: [ ‘ghi’ ]

Create Port on Network (POST /tenant1/network/abc/port)

Port UUID ‘jkl’

Attach Interface to port (PUT /tenant1/network/abc/port/jkl) { ‘attachment’ : ‘ghi’ }

Success

Example Quantum + Nova ArchitectureDashboard /

Automation Tools

Nova Service

XenServer #1

Quantum Pluginnova-api

Hypervisor

vswitch

nova-scheduler

nova-compute

Tenant API Tenant API

Internal PluginCommunication

Internal novaCommunication

Quantum APIQuantumService