OS container object model and management interfaces: The first set of Cloud-Native VNF orchestration specifications2020-11-10 Posted by Jörg Aelken, Rapporteur of ETSI GS NFV-IFA 040 6492 Hits
The ETSI Industry Specification Group (ISG) NFV has published the initial release of ETSI GS NFV-IFA 040 titled "Requirements for service interfaces and object model for OS container management and orchestration specification". This document is the first normative specification delivered for the NFV Release 4 feature on “Cloud-native VNFs and Container Infrastructure management”. The specification propagates the recommendations from the study in ETSI GR NFV-IFA 029 and formally specifies the new functions required for the management and orchestration of OS containers, the Container Infrastructure Service Management (CISM) and the Container Image Registry (CIR). The CISM is responsible for maintaining the containerized workloads while the CIR is responsible for storing and maintaining information of OS container software images.
To enable a consistent and generic system for the management of containerized VNFs, ETSI GS NFV-IFA 040 specifies an abstract NFV object model for OS container management and orchestration, including their relationship to the core information models of NFV-MANO. The abstract NFV objects are also expected to be used in specifications profiling APIs of de-facto standard solutions, to map the abstract NFV objects to objects of the specific de-facto standard solution. One of the introduced abstract NFV objects is the Managed Container Infrastructure Object (MCIO), an object managed and exposed by the CISM, characterized by the desired and actual state of a containerized workload. Managed objects from Kubernetes® such as Deployment or Service are examples which map to an MCIO. Another new NFV object is the Managed Container Infrastructure Object Package (MCIOP), a hierarchical aggregate of information objects including declarative descriptors and configuration files for one or multiple MCIOs. Helm charts as specified by CNCF® are an example which maps to an MCIOP.
Furthermore, ETSI GS NFV-IFA 040 specifies requirements on the list of services to be offered by architectural elements providing the CISM and CIR functions and on the interfaces for exposing these services to NFV-MANO and other consuming entities. The CISM shall provide services for the management of OS container workloads as well as for the management of OS container compute, storage, network resources and their configuration. The CIR shall provide a service for the management of OS container images. This document intentionally does not specify interface operations or information models but only requirements on the management service interfaces. This approach leaves further details to the specification of protocols and data models in the form of profiling de-facto standard open source solutions.