StarOS provides a northbound NETCONF interface that supports a YANG data model for transferring configuration and operational data with the Cisco Network Service Orchestrator (NSO). It also incorporates a ConfD engine to communicate with the NSO management console.
NETCONF (Network Configuration Protocol) is a network management protocol developed and standardized by the IETF (RFC 6241). It provides mechanisms to install, manipulate, and delete the configuration of network devices. Its operations are realized on top of a simple remote procedure call (RPC) layer. The NETCONF protocol uses XML-based data encoding for the configuration data as well as the protocol messages. The protocol messages are exchanged on top of a secure transport protocol.
ConfD is an on-device management framework that provides a set of interfaces to manage a device. The ConfD framework automatically renders all the management interfaces from a data-model. ConfD implements the full NETCONF specification and runs over SSH with content encoded in XML.
ConfD is configured to allow only authenticated/authorized access through external authentication. ConfD Manager provides a standalone CLI module for ConfD to invoke when authenticating/authorizing any new users. ConfD is configured to allow only authorized access through StarOS authentication. Upon authentication, the user is given a privilege level (0-15) which is mapped to StarOS secure admin, admin, operator, and inspector, as defined in the YANG model. StarOS logs CLI authentication event/status messages for each ConfD authentication request.
On the southbound side, ConfD communicates with a StarOS process called via a set of APIs provided by the ConfD management agent. The ConfD Configuration Database (CDB) is used by ConfD to store objects. StarOS accesses the database through the ConfD-supplied APIs. Once the ConfD configuration database is populated, StarOS continues to allow CLI access to modify the overall configuration. There are no automatic updates to the CDB as a result. The CDB only receives updates via the NETCONF interface. In order to keep the CDB and the StarOS configuration databases in sync, all changes made via CLI access (external to NETCONF) to YANG model supported configuration objects must be applied to the CDB manually.
YANG is a data modeling language for the NETCONF network configuration protocol. It can be used to model both configuration data as well as state data of network elements. YANG can also be used to define the format of event notifications emitted by network elements and it allows data modelers to define the signature of remote procedure calls that can be invoked on network elements via the NETCONF protocol (RFC 6020). The YANG file is compiled as part of StarOS and incorporates a subset of the existing StarOS supported CLI commands.
In this release, the YANG model supports a limited set of ECS configuration commands via NSO. For additional information, refer to NSO user documentation and Supported StarOS ECS Configuration Commands.