DEVNET-2005Using the Cisco Open SDN Controller RESTCONF APIs

Using the Cisco Open SDN Controller Restconf APIs

Giles Heron – Principal Engineer

3© 2015 Cisco and/or its affiliates. All rights reserved. Cisco PublicPresentation ID

• The Cisco Open SDN Controller• YANG, and Model Driven APIs• RESTCONF• Demo• Developer support• Additional Resources

Agenda

© 2015 Cisco and/or its affiliates. All rights reserved. Cisco PublicPresentation ID

The Cisco Open SDN Controller

• Based on OpenDaylight Helium• Packaged as a Virtual Machine• Key MD-SAL features pre-installed

• OpenFlow, NETCONF/YANG, BGP, PCEP, etc.

• Integrated User Interface, logging, clustering support• Standalone node or 3-node cluster

• Limited Availability Release as of April 30th, 2015

• Various demos here at DevNet

Cisco’s commercial distribution of the OpenDaylight SDN Controller


• Open platform for network programmability

• Enables SDN for networks at any size and scale

• Selection of southbound protocols (not just OpenFlow)

• Users can add value at any layer (Apps, Network Services, SB Plugins)

OpenDaylight Controller

Cisco Contributions


“Just for the YANG of it”

• YANG is a data modeling language• Documented in RFC6020• Designed to model NETCONF data (see RFC6241)

• OpenDaylight’s MD-SAL is “Model Driven Service Abstraction Layer”• “Model” == YANG Model

• OpenDaylight Helium contains over 300 YANG models• YANG is used as our IDL

• Southbound plugins described by YANG Models• NETCONF plugin learns models from connected devices at run-time

Everything in MD-SAL is YANG modeled


YANG and XML• YANG assumes an XML encoding of instantiated information

• Defines XML rendering rules• Relies on XML encoding for certain advanced features (e.g. expression of constraints

using Xpath)• Facilitates describing XML document hierarchies• Nicely aligned with NETCONF

• YANG itself is not XML• Emphasis on readability

• Familiar structure to C/C++ or Java programmers• XML notation exists: YIN (Yang-Independent Notation)

• Semantic equivalence • Syntactic conversions YANG <-> YIN

• Alternative encodings defined (e.g. JSON for RESTconf)


YANG

• Data modeling language• Configuration data• State data

• Tree structure

• Data and Types

acme-box module

properties container

interfaces container

name: string, config

name: string, config

interface: list, key = name

oper-state: enum, config


ODL

Transport

RemoteOperations

MgmtServices

Mgmt info(encoding)

Mgmt info(definition)

XML-encoded content

YANG modules

NETCONF operations

XMLRPC

TLS,SSH

JSON JAVA DTO

I2RS

?

HTTP

RESTCONF

TCP

YANG - NETCONF, RESTCONF, I2RS & IDL


Controller

YANG IDL – OpenDaylight MD-SAL

MD-SAL

DOM BrokerBA-BI Connector

Mapping Service

Codec Registry

Schema Service

Codec Generator

Binding-Aware Broker Data Store

Binding-Aware to Binding-Independent Data Translation

Binding-Aware PluginBinding-Independent

Plugin/Client (NETCONF/RESTCONF)

Forwarding Rules Manager, Stats Manager, BGP-LS/PCEP

RESTCONF Clients

Internal Clients

YANG Models


RESTCONF

• REST protocol over HTTP• GET, POST, PUT, DELETE etc.

• For accessing data defined in YANG• Container or List (NOT leaf or leaf-list)

• Using data stores defined in NETCONF• YANG Modules are listed under /restconf/<Module> in top-level API• Config/state classification based on the YANG config statement• Supports XML and JSON

• “Python Programmers Against XML!”

REST API Auto generated from the YANG Models


Resource URI Map/restconf /config /<top-level-data-nodes> (configuration data) /operational /<top-level-data-nodes> (operational data) /modules /module /name /revision /namespace /feature /deviation /operations /<custom protocol operations> /streams /stream /name /description /replay-support /replay-log-creation-time /events /version (field)

Event streams, subscribe using “get”,

can specify filters

Meta-information:Capabilities etc

Meta-information:Supported RPCs

YANG-defined

data


RESTCONF

• Two datastores are accessible:• Config

• /restconf/config/<Module>:<Top Level Container>/….• Operational

• /restconf/operational/<Module>:<Top Level Container>/…

• URL grows as you go down through the models• Can Access any Container or List

• Also support for RPCs• /restconf/operations/<Module>:<RPC> (HTTP POST only)



OSC API Authentication scheme

14

• OSC uses a Token based authentication scheme

• Issue the following request to get a token• https://{{HOST}}/controller-auth?

grant_type=password&username={{user}}&password={{password}}&scope=sdn• Response: {"expires_in":86400000,"token_type":"Bearer","access_token":"a304e0f0-ad68-3d93-

8986-cd775f3b9949"}

• Subsequent requests need the Basic Authorization Header of the form: "token:<token>”

• Here is a fragment of Javascript to automate the processvar data = JSON.parse(responseBody);postman.setGlobalVariable("token", data.access_token);var creds = btoa("token:" + data.access_token);postman.setGlobalVariable("Authorization", "Basic " + creds);


Mounting Remote DatastoresOpenDaylight Controller Config

MD-SAL

NETCONF

NETCONF

• Mounted under e.g. http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/controller-config

• Data can be accessed using …/yang-ext:mount/…

• …/yang-ext:mount/config:modules is used to configure the various plug-ins

Config Store

RESTCONF


Mounting Remote DatastoresOpenDaylight NETCONF Node “Discovery”

MD-SAL

NETCONF

RESTCONF

Node Inventory

• Nodes added by POSTing to config:modules

• ODL connects to each node

• ODL learns capabilities (YANG modules) and stores to model cache• Cache at ~/cache/schema. Filenames of form [email protected].

Model Cache

XR1 XR2 OpenWRT


Mounting Remote DatastoresOpenDaylight NETCONF Node Configuration

MD-SAL

NETCONF

RESTCONF

Node Inventory

• Nodes configured by POSTing or PUTting to e.g.:• http://localhost:8181/restconf/config/o

pendaylight-inventory:nodes/node/XR2/yang-ext:mount/Cisco-IOS-XR-ifmgr-cfg:interface-configurations/interface-configuration/act/Loopback0/

• Can retrieve config (or operational stats) using GET

Model Cache

XR1 XR2 OpenWRT

http://localhost:8181/restconf/config/opendaylight-inventory:nodes/node/XR2/yang-ext:mount/





Open SDN Controller YANG Models/APIs

• Inventory• Mounted NETCONF Devices• BGP• PCEP• Topology• OpenFlow


© 2015 Cisco and/or its affiliates. All rights reserved. Cisco PublicPresentation ID 19

Demo

© 2015 Cisco and/or its affiliates. All rights reserved. Cisco PublicPresentation ID 20

Devnet Portal for Cisco Open SDN Controllerdeveloper.cisco.com/site/openSDN

Documentation

API Reference Guides

Video

Code samples

Sandbox environment

Thank you

21© 2015 Cisco and/or its affiliates. All rights reserved. Cisco PublicPresentation ID

Technology

DEVNET-2005Using the Cisco Open SDN Controller RESTCONF APIs