RESTCONF and APIs

RESTCONF (RFC 8040) is an HTTP-based protocol for accessing network configuration and state data defined by YANG models. It brings the simplicity and familiarity of REST APIs to network management. Beyond RESTCONF, many network vendors and controllers offer their own REST APIs for automation.

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What is RESTCONF?

RESTCONF is essentially NETCONF over HTTP. It uses the same YANG data models but replaces XML-over-SSH with HTTP methods and JSON or XML encoding:

Feature	NETCONF	RESTCONF
Transport	SSH (port 830)	HTTPS (port 443)
Encoding	XML	JSON or XML
Operations	RPC-based	HTTP methods (GET, POST, PUT, PATCH, DELETE)
URL structure	XPath / subtree filters	RESTful resource URIs
Tooling	ncclient (Python)	Any HTTP client (curl, requests, Postman)
Ease of use	Medium	High — familiar to web developers

HTTP Methods Mapping

HTTP Method	RESTCONF Operation	Description
GET	Read	Retrieve configuration or operational data
POST	Create	Create a new resource
PUT	Create or Replace	Create or completely replace a resource
PATCH	Update (Merge)	Partially update a resource
DELETE	Delete	Remove a resource

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RESTCONF URL Structure

The RESTCONF URL follows the YANG model hierarchy:

https://<device>/restconf/data/<module>:<container>/<list>=<key>/<leaf>

Examples

URL	Description
/restconf/data/ietf-interfaces:interfaces	All interfaces
/restconf/data/ietf-interfaces:interfaces/interface=GigabitEthernet1	A specific interface
/restconf/data/Cisco-IOS-XE-native:native/hostname	Device hostname
/restconf/data/openconfig-network-instance:network-instances	Routing instances

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Using RESTCONF with curl

Get All Interfaces

curl -k -u admin:secret \
  -H "Accept: application/yang-data+json" \
  https://192.168.1.1/restconf/data/ietf-interfaces:interfaces

Get a Specific Interface

curl -k -u admin:secret \
  -H "Accept: application/yang-data+json" \
  https://192.168.1.1/restconf/data/ietf-interfaces:interfaces/interface=GigabitEthernet1

Create an Interface (PUT)

curl -k -u admin:secret \
  -X PUT \
  -H "Content-Type: application/yang-data+json" \
  -d '{
    "ietf-interfaces:interface": {
      "name": "Loopback99",
      "description": "Created via RESTCONF",
      "type": "iana-if-type:softwareLoopback",
      "enabled": true
    }
  }' \
  https://192.168.1.1/restconf/data/ietf-interfaces:interfaces/interface=Loopback99

Update an Interface (PATCH)

curl -k -u admin:secret \
  -X PATCH \
  -H "Content-Type: application/yang-data+json" \
  -d '{
    "ietf-interfaces:interface": {
      "name": "Loopback99",
      "description": "Updated via RESTCONF"
    }
  }' \
  https://192.168.1.1/restconf/data/ietf-interfaces:interfaces/interface=Loopback99

Delete an Interface

curl -k -u admin:secret \
  -X DELETE \
  https://192.168.1.1/restconf/data/ietf-interfaces:interfaces/interface=Loopback99

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Using RESTCONF with Python

import requests
import json

# Disable SSL warnings (lab only)
requests.packages.urllib3.disable_warnings()

BASE_URL = "https://192.168.1.1/restconf"
HEADERS = {
    "Accept": "application/yang-data+json",
    "Content-Type": "application/yang-data+json",
}
AUTH = ("admin", "secret")

def get_interfaces():
    """Retrieve all interfaces via RESTCONF."""
    url = f"{BASE_URL}/data/ietf-interfaces:interfaces"
    response = requests.get(url, headers=HEADERS, auth=AUTH, verify=False)
    response.raise_for_status()
    return response.json()