The Nokia SR OS YANG modules are the base for the model-driven architecture.
SR OS configuration is divided into several top level configuration regions (see Datastores and regions for details). The data models for each configuration region are separated into different YANG modules.
The primary configuration region (configure) is modeled in the nokia-conf YANG module specified in a single file located at YANG/nokia-combined/nokia-conf.yang in the SR OS image distribution.
An alternative packaging of the primary configuration region is also available as a set of submodules (for example, nokia-conf-system) that belong to a single module located at YANG/nokia-conf.yang in the SR OS image distribution. The submodules have independent revision dates and can be used to identify which parts of the configuration model have changed.
The packaging options (combined and submodule) are alternate representations of the same data model. There is no difference between using the combined or submodule packaging for all the basic configuration or state operations (including with telemetry). The same containers, list, leafs, and so on, exist in the same namespaces whether you are using the combined or submodule packaging. The main difference between the combined and submodule options is seen in the NETCONF <hello>, YANG library, and <get-schema> data where there are lists of modules and submodules.
Some YANG tools may show errors about circular dependencies in the submodules. For example, Pyang gives an error about circular dependencies but does complete the processing to build complete tree or jstree output. If circular dependencies are preventing any necessary tools from correctly processing the YANG, use the combined packaging instead of the submodules. For details about enabling various sets of YANG modules, see the yang-modules commands in the 7450 ESS, 7750 SR, 7950 XRS, and VSR Classic CLI Command Reference Guide.
The lawful intercept (LI) configuration region is modeled in the nokia-li-conf YANG module specified in a single file called nokia-li-conf.yang.
The BOF configuration region is modeled in the nokia-bof-conf YANG module specified in a single file called nokia-bof-conf.yang.
SR OS state information is modeled in the nokia-state YANG module specified in a single file located at YANG/nokia-combined/nokia-state.yang in the SR OS image distribution.
LI state information is modeled in nokia-li-state.yang which augments the primary nokia-state module.
BOF state information is modeled in nokia-bof-state.yang.
There are also a series of nokia-types-* modules that are included by various configuration and state modules.
The SR OS YANG modules have the following attributes.
The modules can be used with NETCONF, telemetry, or with the Set/Get RPCs of the gRPC-based gNMI service.
The modules and submodules indicate the SR OS major release stream using a YANG extension (for example, sros-ext:sros-major-release "rel16";). Module and submodule revisions form a contiguous series of revisions inside a major release stream. There may be two files for the same module with the same revision date but with different contents because they are from two different major release streams. Each active major release stream has revisions ongoing in parallel.
All configuration modules, state modules, and types modules are advertised in the SR OS NETCONF server <hello>. Submodules are not advertised in the <hello>.
The classic CLI clear, show, monitor, and tools branches of the CLI do not have equivalent YANG data models.
Some admin and file operations have YANG models whereby each operation is modeled using a YANG ‟action” statement. These can be viewed in the nokia-oper-*.yang files. See YANG-modeled operations for more information.