1. Description:
This document describes about how to derive yang path from a yang module. It’s challenging to get the sensor path info from the yang modules containing data models. Below section explains about how to get the a data model from a Yang module.
This can be used for both Cisco and openconfig specific yang modules.
Yang is a data modeling language used to model configs and provide real time state data.
2. Summary
- Install Pyang
- Download yang modules from git
- Using pyang derive the path
- Configure on xr router and validate
3. Detailed steps using pyang to derive the path
3.1 Get pyang using “pip install pyang”
3.2 Use the below github link to clone or download
https://github.com/YangModels/yang.git
NARVENKA$ git clone https://github.com/YangModels/yang.git
Cloning into 'yang'...
remote: Enumerating objects: 2, done.
remote: Counting objects: 100% (2/2), done.
remote: Compressing objects: 100% (2/2), done.
remote: Total 21976 (delta 0), reused 1 (delta 0), pack-reused 21974
Receiving objects: 100% (21976/21976), 42.41 MiB | 3.48 MiB/s, done.
Resolving deltas: 100% (17077/17077), done.
Checking out files: 100% (20902/20902), done.
NARVENKA$
3.3 Browse through the directory:
NARVENKA$ cd yang/
NARVENKA$ ls
README.md experimental setup.py standard testall.sh tools vendor
NARVENKA$ cd vendor/
NARVENKA$ cd cisco/
NARVENKA$ ls
README.md check.sh common nx xe xr
NARVENKA$ cd xr/
NARVENKA$ ls
530 533 601 612 622 632 651
531 534 602 613 623 641 README.md
532 600 611 621 631 642 check.sh
NARVENKA$ cd 651/
NARVENKA$ pwd
/Users/macuser/yang/vendor/cisco/xr/651
3.4 Based on the requirement select the yang model from
https://github.com/YangModels/yang/tree/master/vendor/cisco/xr
3.5 Using pyang construct yang path
<Modulename:yang tree with leaf>
Cisco-IOS-XR-qos-ma-oper:qos/interface-table/interface/member-interfaces/member-interface/output
NARVENKA$ pyang -f tree Cisco-IOS-XR-qos-ma-oper.yang --tree-depth=1
module: Cisco-IOS-XR-qos-ma-oper
+--ro qos
...
NARVENKA$ pyang -f tree Cisco-IOS-XR-qos-ma-oper.yang --tree-path=qos --tree-depth=2
module: Cisco-IOS-XR-qos-ma-oper
+--ro qos
+--ro nv-interface-table
| ...
+--ro nv-satellite
| ...
+--ro nodes
| ...
+--ro qos-global
| ...
+--ro interface-table
...
NARVENKA$ pyang -f tree Cisco-IOS-XR-qos-ma-oper.yang --tree-path=qos/interface-table --tree-depth=3
module: Cisco-IOS-XR-qos-ma-oper
+--ro qos
+--ro interface-table
+--ro interface* [interface-name]
...
NARVENKA$ pyang -f tree Cisco-IOS-XR-qos-ma-oper.yang --tree-path=qos/interface-table/interface --tree-depth=4
module: Cisco-IOS-XR-qos-ma-oper
+--ro qos
+--ro interface-table
+--ro interface* [interface-name]
+--ro nodes
| ...
+--ro interface-name xr:Interface-name
+--ro member-interfaces
| ...
+--ro satellite-ids
| ...
+--ro input
| ...
+--ro output
...
NARVENKA$ pyang -f tree Cisco-IOS-XR-qos-ma-oper.yang --tree-path=qos/interface-table/interface/member-interfaces --tree-depth=5
module: Cisco-IOS-XR-qos-ma-oper
+--ro qos
+--ro interface-table
+--ro interface* [interface-name]
+--ro member-interfaces
+--ro member-interface* [interface-name]
...
NARVENKA$ pyang -f tree Cisco-IOS-XR-qos-ma-oper.yang --tree-path=qos/interface-table/interface/member-interfaces/member-interface --tree-depth=6
module: Cisco-IOS-XR-qos-ma-oper
+--ro qos
+--ro interface-table
+--ro interface* [interface-name]
+--ro member-interfaces
+--ro member-interface* [interface-name]
+--ro interface-name xr:Interface-name
+--ro satellite-ids
| ...
+--ro input
| ...
+--ro output
...
NARVENKA$ pyang -f tree Cisco-IOS-XR-qos-ma-oper.yang --tree-path=qos/interface-table/interface/member-interfaces/member-interface/output --tree-depth=7
module: Cisco-IOS-XR-qos-ma-oper
+--ro qos
+--ro interface-table
+--ro interface* [interface-name]
+--ro member-interfaces
+--ro member-interface* [interface-name]
+--ro output
+--ro service-policy-names
...
NARVENKA$
4. Construct sensor path and validate data model
Now construct the sensor path including tree with respective leaf. In XR node sensor path configured under sensor group. Please refer the below example for validation.
sensor-path Cisco-IOS-XR-qos-ma-oper:qos/interface-table/interface/member-interfaces/member-interface/output
Example:
RP/0/RSP0/CPU0:BX03#conf terminal
RP/0/RSP0/CPU0:BX03(config)#telemetry model-driven
RP/0/RSP0/CPU0:BX03(config-model-driven)#sensor-group 1minute
RP/0/RSP0/CPU0:BX03(config-model-driven-snsr-grp)# sensor-path Cisco-IOS-XR-qos-ma-oper:qos/interface-table/interface/member-interfaces/member-interface/output
RP/0/RSP0/CPU0:BX03(config-model-driven-snsr-grp)#commit
RP/0/RSP0/CPU0:Sep 25 20:20:41.691 UTC: config[66977]: %MGBL-CONFIG-6-DB_COMMIT : Configuration committed by user 'narvenka'. Use 'show configuration commit changes 1000000386' to view the changes.
RP/0/RSP0/CPU0:BX03(config-model-driven-snsr-grp)#end
RP/0/RSP0/CPU0:Sep 25 20:20:43.069 UTC: config[66977]: %MGBL-SYS-5-CONFIG_I : Configured from console by narvenka
RP/0/RSP0/CPU0:BX03#
RP/0/RSP0/CPU0:BX03#
RP/0/RSP0/CPU0:BX03#show telemetry model-driven subscription
Subscription: 1minute State: NA
-------------
Sensor groups:
Id Interval(ms) State
1minute 60000 Resolved
RP/0/RSP0/CPU0:BX03#show telemetry model-driven subscription detail
Subscription:
-------------
State: NA
Collection Groups:
------------------
No active collection groups
RP/0/RSP0/CPU0:BX03#show telemetry model-driven subscription 1minute
Subscription: 1minute
-------------
State: NA
Sensor groups:
Id: 1minute
Sample Interval: 60000 ms
Sensor Path: Cisco-IOS-XR-asr9k-np-oper:hardware-module-np/nodes/node/nps/np/load-utilization
Sensor Path State: Resolved
Sensor Path: Cisco-IOS-XR-telemetry-model-driven-oper:telemetry-model-driven/destinations/destination
Sensor Path State: Resolved
Sensor Path: Cisco-IOS-XR-qos-ma-oper:qos/interface-table/interface/member-interfaces/member-interface/output
Sensor Path State: Resolved
Collection Groups:
------------------
No active collection groups
RP/0/RSP0/CPU0:BX03#
Also refer “Implementing GRPC/Telemetry on XR devices” for more info about implementation.
