Facing error while running pyang for updating YDK model in Cafykit env

[vgavali]

I am updating YDK model in Cafykit environment using this wiki https://wwwin-github.cisco.com/cafy/cafykit/wiki/YDK-model-updation-in-Cafykit-environment Facing below errors while running the pyang. 

ietf-datastores.yang:2: error: bad value "1.6" (should be version)
ietf-yang-library.yang:2: error: bad value "1.1" (should be version)
ietf-yang-library.yang:9: error: unexpected keyword "reference"
ietf-yang-library.yang:14: error: unexpected keyword "reference"
ietf-yang-library.yang:20: error: unexpected keyword "reference"
openconfig-interfaces.yang:177: error: openconfig-bfd:interface in the path for subinterface at openconfig-bfd.yang:742 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-bfd:interface in the path for subinterface at openconfig-bfd.yang:742 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-if-tunnel:interface in the path for subinterface at openconfig-if-tunnel.yang:118 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-if-tunnel:interface in the path for subinterface at openconfig-if-tunnel.yang:118 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-if-tunnel:interface in the path for subinterface at openconfig-if-tunnel.yang:118 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-if-tunnel:interface in the path for subinterface at openconfig-if-tunnel.yang:118 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-network-instance:interface in the path for subinterface at openconfig-network-instance.yang:1000 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-network-instance:interface in the path for subinterface at openconfig-network-instance.yang:1000 (at openconfig-interfaces.yang:173) is not found
openconfig-interfaces.yang:177: error: openconfig-network-instance:interface in the path for subinterface at openconfig-network-instance.yang:1000 (at openconfig-interfaces.yang:173) is not found

Please assist if you have faced such errors in the past or know the resolution for them.

Thanks,

Vishakha

[yangorelik]

You need upgrade to YDK 0.8.6, which has limited support for YANG-1.1 features. That would allow the pyang version 2.5 to process YANG-1.1 modules.

[vgavali · Accepted solution]

Found the fix. I deleted the yang files which gave error messages. Eg. rm ietf-datastores.yang and so on, and reran the pyang. The rerun again gave some errors for which I again deleted the errored yang files. Kept repeating the process until there were no further errors. I was successful after 15 attempts. (This fix was suggested by the model support team)