# OpenConfig to device config mapping

# Finding mapping between device and the model

Preferred YANG models for device config and operational data are OpenConfig models.

These models usually represent configuration part in container config and operational part in container state. Operational data is config data + operational data.

YANG models used in UniConfig framework need to be located in https://github.com/FRINXio/openconfig. In case the desired functionality is not modeled yet, you can create new YANG with its own structure or it can augment existing OpenConfig models. Guideline, how to write OpenConfig models can be found at http://www.openconfig.net/docs/style-guide/.

# Choosing the right YANG models

Before writing a custom YANG model for a unit, it is important to check whether such a model doesn't already exist. There are plenty of YANG models available, modeling many aspects of network device management. The biggest groups of models are:

It is usually wiser to choose an existing YANG model instead of developing a custom one. Also, it is very important to check for existing units already implemented for a device. If there are any, the best approach will most likely be to use YANG models from the same family as existing units use.

# Existing documentation

There is translation-units-docs page as a single point of truth for mapping. Use `` notation for variables in the templates. This notation is postman compatible.