Solved: Re: Module Error with pyang sample-xml-skeleton and IOS-XE YANG models

DrSchw0b · ‎10-25-2022

Hi,

I am new to YANG/Netconf. Apologies in advance if there is an obvious answer to my question.

I am using the Yang models of the https://github.com/YangModels/yang repositories, Python 3.9.2 and pyang 2.5.3 for the following:

I am trying to get a feeling for the YANG models in combination with Netconf. I came across pyang with the “sample-xml-skeleton” format. As a beginner this looks to me as approach to get the XML template, I might use to correctly format the Netconf payload. In fact, I succeed to do so with the IETF interfaces YANG model:

pyang -t edit -f sample-xml-skeleton yang/standard/ietf/RFC/ietf-interfaces.yang --sample-xml-skeleton-defaults

After that I tried to get a “template” for IOS-XE ntp servers:

$ pyang -f sample-xml-skeleton yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ntp.yang --sample-xml-skeleton-defaults
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ntp.yang:5: error: module "cisco-semver" not found in search path
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ntp.yang:11: error: module "Cisco-IOS-XE-types" not found in search path
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ntp.yang:14: error: module "Cisco-IOS-XE-native" not found in search path
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ntp.yang:17: error: module "Cisco-IOS-XE-interface-common" not found in search path
sample-xml-skeleton plugin needs a valid module

As you can see, I got an error message.

I also tried running the command in the respective YANG Model folder or by adding the path parameter to the command. Both generated the (more or less) same warning messages:

cd yang/vendor/cisco/xe/1781/
pyang -f sample-xml-skeleton Cisco-IOS-XE-ntp.yang --sample-xml-skeleton-defaults
[output omitted]

==============================
pyang -t edit -f sample-xml-skeleton -p yang/vendor/cisco/xe/1781/ yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ntp.yang --sample-xml-skeleton-defaults
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:636): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:1620): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:1623): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:1635): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:1782): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:1785): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:1962): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:2420): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:3944): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:4031): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:4155): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:4449): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:5556): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:5559): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:5572): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:5751): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:5754): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:5941): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2592 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-interfaces.yang:6310): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-interfaces"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1615): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1790): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1793): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1796): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1799): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1802): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1805): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1808): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1811): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1814): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1817): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1820): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1823): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1826): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1829): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1832): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1835): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1838): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1876): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1879): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1882): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1885): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1888): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1891): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1894): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1897): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1900): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1903): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1906): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1909): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1912): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1915): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1918): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1921): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:1924): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:3232): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:3288): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2543 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ip.yang:3816): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ip"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2565 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ipv6.yang:503): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ipv6"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2565 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-ipv6.yang:527): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-ipv6"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:235): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:244): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:673): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:728): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:860): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:922): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:1120): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:1135): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:1168): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
yang/vendor/cisco/xe/1781/Cisco-IOS-XE-native.yang:2862 (at yang/vendor/cisco/xe/1781/Cisco-IOS-XE-logging.yang:1183): warning: node "Cisco-IOS-XE-native::native" is not found in module "Cisco-IOS-XE-logging"
<?xml version='1.0' encoding='UTF-8'?>
<data xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"/>

I am now wondering whether there might be an issue with the IOS-XE 17.8.1 YANG models and how to proceed. Any support is very much appreciated. Thank you, a lot, in advance for your support.

DrSchw0b · ‎10-26-2022

Thank you for pointing me into the right direction. I was able to get the required XML "template" with pyang using the following command:

pyang -f sample-xml-skeleton Cisco-IOS-XE-native.yang Cisco-IOS-XE-ntp.yang --sample-xml-skeleton-defaults --sample-xml-skeleton-path=/native/ntp

I learned that the file names of all required models must be passed to pyang for it to work. The "tree" output with a single model might work; however, this model might lack the surrounding element structure. For the NTP servers to be set, the "native" tags must surround the "ntp" element.

View solution in original post

miott · ‎10-25-2022

The ntp model augments the Cisco-IOS-XE-native model so looking directly at the ntp model will give you nothing. I suggest you look at https://developer.cisco.com/yangsuite. Yangsuite will gather together all the model dependencies and give you a visual tree structure to look at. You can also interact with devices using various protocols like NETCONF, RESTCONF, and gNMI.

DrSchw0b · ‎10-26-2022

Thank you for pointing me into the right direction. I was able to get the required XML "template" with pyang using the following command:

pyang -f sample-xml-skeleton Cisco-IOS-XE-native.yang Cisco-IOS-XE-ntp.yang --sample-xml-skeleton-defaults --sample-xml-skeleton-path=/native/ntp

I learned that the file names of all required models must be passed to pyang for it to work. The "tree" output with a single model might work; however, this model might lack the surrounding element structure. For the NTP servers to be set, the "native" tags must surround the "ntp" element.