Welcome to YANG Central

YANG? What's YANG?

YANG is a data modeling language used to model configuration and state data manipulated by the NETCONF protocol (RFC 6241), NETCONF remote procedure calls, and NETCONF notifications.

The YANG language was developed by the IETF NETCONF Data Modeling Language Working Group (NETMOD), and is defined in RFC 7950.

YANG News

2016-09-01: RFC 7952, Defining and Using Metadata with YANG, has been published, see documents page.

2016-09-01: RFC 7951, JSON Encoding of Data Modeled with YANG, has been published, see documents page.

2016-09-01: RFC 7950, YANG 1.1, has been published, see documents page.

2016-07-01: RFC 7895, YANG Module Library, has been published, see documents page.

2016-04-04: Updated the tools page with NETCONF/YANG clients and servers.

2016-02-01: Updated the tools page with more tools.

2015-09-30: Updated the tools page.

2014-12-18: RFC 7407, A YANG Data Model for SNMP Configuration, has been published, see documents page.

2014-08-07: RFC 7317, A YANG Data Model for System Management, has been published, see documents page.

2014-06-16: RFC 7277, A YANG Data Model for IP Management, has been published, see documents page.

2014-05-16: RFC 7223, A YANG Data Model for Interface Management, has been published, see documents page.

2013-12-11: More tutorials available on the documents page.

2011-10-04: Added a VIM syntax file to the tools page. Thanks to Matt Parker!

2011-03-26: NETCONF, YANG and DSDL mapping was presented at the XML Prague 2011 conference. Proceedings are available online.

2011-02-16: Updated DSDLMappingTutorial to be in sync with pyang 1.1.

2011-02-15: Updated all Examples to be RFC 6020 compliant.

2011-02-14: The YANG to DSDL mapping specification is now published as RFC 6110.

2011-01-31: Guidelines for YANG module authors RFC 6087.

2010-10-07: The pyang tool is now released as version 1.0, RFC 6020 compatible.

2010-10-06: The YANG specification is now published as RFC 6020, and YANG types as RFC 6021.

2010-06-18: The latest YANG draft (draft-ietf-netmod-yang-13) and YANG types draft (draft-ietf-netmod-yang-types-09) have been accepted and are now in the RFC editor's queue. See YangDocuments for more info.

2010-04-14: A new updated version (draft-ietf-netmod-yang-12) has been published. See YangDocuments for more info.

2010-01-12: A new updated version (draft-ietf-netmod-yang-10) has been published. See YangDocuments for more info.

2009-10-15: Added a new tutorial from IETF75, updated YangDocuments with pointers to the latest YANG documents.

2009-06-24: Added a link to the jYang Java implementation. See YangTools for more info.

2009-04-20: A new updated version (draft-ietf-netmod-yang-05) has been published. See YangDocuments for more info.

2009-01-12: A new updated version (draft-ietf-netmod-yang-03) has been published. See YangDocuments for more info.

2008-11-04: Added link to the standard YANG types document. See YangDocuments for more info.

2008-11-04: Updated examples and tutorial so they are compliant with the current spec.

2008-11-03: draft-ietf-netmod-yang-02 published. See YangDocuments for more info.

2008-04-29: The IETF NETMOD WG is formed to develop the YANG data modeling language for NETCONF.

2008-03-12: Added a page comparing YANG to alternatives.

2008-02-18: draft-bjorklund-yang-requirements-00 published. See YangDocuments for more info.

2008-02-06: draft-bjorklund-netconf-yang-02 published. The pyang validator is updated to this version.

A quick YANG example

This is a simple example of what a YANG module looks like:

module acme-system {
    namespace "http://acme.example.com/system";
    prefix "acme";

    organization "ACME Inc.";
    contact "joe@acme.example.com";
    description
        "The module for entities implementing the ACME system.";

    revision 2007-11-05 {
        description "Initial revision.";
    }

    container system {
        leaf host-name {
            type string;
            description "Hostname for this system";
        }

        leaf-list domain-search {
            type string;
            description "List of domain names to search";
        }

        list interface {
            key "name";
            description "List of interfaces in the system";
            leaf name {
                type string;
            }
            leaf type {
                type string;
            }
            leaf mtu {
                type int32;
            }
        }
    }
}