opx-base-model

This repository contains the YANG models which define the object model for all software components.

Model overview

Applications/scripts can use existing models, and build new models for behavior on the system. Read the Application Programming Guide for more information on CPS interfaces.

The YANG class parser goes through each file and generates:

1. C/C++ header files with all class names and attributes, enums, typedefs, and so on. 

2. C++ metadata files compiled to loadable models which are available to CPS-enabled applications.

3. XML files with metadata can be used by other languages for which loadable models are not suitable.

NOTE: The name of the YANG model is generally reflected in the symbol prefix — class names, types, enums, and so on. We describe how to map YANG classes and attributes to C/C++ headers in the documentation.

Where are the outputs?

Good question...there are two main packages created from this source repository:

• libopx-base-model-dev — model header files
• libopx-base-model1 — model meta data in compiled format

After installing the libopx-base-model-dev, the header files are stored in the /usr/include/opx folder (unless you change the prefix).

The library metadata files are stored in the usr/lib/x86_64-linux-gnu/ directory (assuming default Debian 64-bit build).

You can see the metadata from Python using the cps.type API, or the cps.info API or one of the many other Python extension APIs.

Adding a new model

To add a new model to the system, add a model file into the yang-model directory:

1. Create a new YANG model (extension should be .yang).

2. Copy the YANG model into the yang-model directory.

3. Update the makefile.ini with the appropriate model.

4. Run the build.

Changing/enhancing a model

Adding attributes and deleting attributes are as easy as modifying the model, and recompiling.

The history files need to be kept in sync with the YANG model — that history file provides upgradability between model changes.

Using models

Platform example

Use a class from the dell-base-pas.yang model:

• The model prefix is base-pas, and the class we want to use in this example is entity
• The key for the entity class (within the dell-base-pas.yang) is base-pas/entity

Networking example

Let's say that an application needs to get the LAG interfaces via script (ignoring that the LAG can be queried through the Linux bonding commands). The interface class that holds the LAG information is in the dell-base-if.yang file.

• In this file, the class is actually an augment of the /if:interfaces/if:interface
• Prefix in the file is dell-base-if-cmn

Since the mode is an augment, normally you would communicate using the key from the augmented object which is in this case if/interfaces/interface.

Looking at the details in the YANG model (description) itself (dell-base-if.yang), the documentation states that access to the class can be through the dell-base-if-cmn/if/interfaces/interface model.

From a CPS perspective, you can use the key dell-base-if-cmn/if/interfaces/interface.

It also states that to do a query of LAG interfaces — you need to specify the ietf interface type.

Using the cps_get_oid.py script you would use:   

cps_get_oid.py target dell-base-if-cmn/if/interfaces/interface if/interfaces/interface/type=ianaift:ieee8023adLag

Models

Platform models

• dell-base-platform-common.yang
• dell-base-env-tempctl.yang 
• dell-base-media.yang           
• dell-base-pas.yang

Management interface (eth0)

• dell-base-mgmt-interface.yang  

Network models

• ACL and QoS configurations
• dell-base-acl.yang 

Networking interfaces

The following set of models provides the networking access-related models/classes:

• dell-base-if.yang         
• dell-base-if-lag.yang      
• dell-base-if-phy.yang      
• dell-base-if-vlan.yang    
• dell-base-if-mgmt.yang    
• dell-base-if-linux.yang   
• dell-base-qos.yang
• dell-base-ip.yang               
• dell-base-routing.yang
• dell-base-l2-mac.yang          
• dell-base-sflow.yang
• dell-base-lag.yang             
• dell-base-statistics.yang
• dell-base-stg.yang
• dell-base-switch-element.yang
• dell-base-mirror.yang          
• dell-base-vlan.yang
• dell-base-packet.yang           
• dell-interface.yang

(c) 2017 Dell