5. Guidelines Addendum for 2019.12 release

5.1. Introduction

This addendum provides a high-level description of the testing scope and pass/fail criteria used in the OPNFV Verification Program (OVP) for the 2019.12 release. This information is intended as an overview for OVP testers and for the Dovetail Project to help guide test-tool and test-case development for the OVP 2019.12 release. The Dovetail project is responsible for documenting test-case specifications as well as implementing the OVP tool-chain through collaboration with the OPNFV testing community. OVP testing focuses on establishing the ability of the System Under Test (SUT) to perform NFVI and VIM operations and support Service Provider oriented features that ensure manageable, resilient and secure networks.

5.2. Meaning of Compliance

OPNFV Compliance indicates adherence of an NFV platform to behaviors defined through specific platform capabilities, allowing to prepare, instantiate, operate and remove VNFs running on the NFVI. OVP 2019.12 compliance evaluates the ability of a platform to support Service Provider network capabilities and workloads that are supported in the OPNFV platform as of this release. Compliance test cases are designated as compulsory or optional based on the maturity of OPNFV capabilities as well as industry expectations. Compulsory test cases may for example include NFVI management capabilities whereas tests for certain high-availability features may be deemed as optional.

Test coverage and pass/fail criteria are designed to ensure an acceptable level of compliance but not be so restrictive as to disqualify variations in platform implementations, capabilities and features.

5.3. SUT Assumptions

Assumptions about the System Under Test (SUT) include …

  • The minimal specification of physical infrastructure, including controller nodes, compute nodes and networks, is defined by the Pharos specification.
  • The SUT is fully deployed and operational, i.e. SUT deployment tools are out of scope of testing.

5.4. Scope of Testing

The OVP Governance Guidelines, as approved by the Board of Directors, outlines the key objectives of the OVP as follows:

  • Help build the market for
    • OPNFV based infrastructure
    • applications designed to run on that infrastructure
  • Reduce adoption risks for end-users
  • Decrease testing costs by verifying hardware and software platform interfaces and components
  • Enhance interoperability

The guidelines further directs the scope to be constrained to “features, capabilities, components, and interfaces included in an OPNFV release that are generally available in the industry (e.g., through adoption by an upstream community)”, and that compliance verification is evaluated using “functional tests that focus on defined interfaces and/or behaviors without regard to the implementation of the underlying system under test”.

OPNFV provides a broad range of capabilities, including the reference platform itself as well as tools-chains and methodologies for building infrastructures, and deploying and testing the platform. Not all these aspects are in scope for OVP and not all functions and components are tested in the initial versions of OVP. For example, the deployment tools for the SUT and CI/CD toolchain are currently out of scope. Similarly, performance benchmarking related testing is also out of scope or for further study. Newer functional areas such as MANO (outside of APIs in the NFVI and VIM) are still developing and are for future considerations.

5.4.1. General Approach

In order to meet the above objectives for OVP, we aim to follow a general approach by first identifying the overall requirements for all stake-holders, then analyzing what OPNFV and the upstream communities can effectively test and verify presently to derive an initial working scope for OVP, and to recommend what the community should strive to achieve in future releases.

The overall requirements for OVP can be categorized by the basic cloud capabilities representing common operations needed by basic VNFs, and additional requirements for VNFs that go beyond the common cloud capabilities including functional extensions, operational capabilities and additional carrier grade requirements.

For the basic NFV requirements, we will analyze the required test cases, leverage or improve upon existing test cases in OPNFV projects and upstream projects whenever we can, and bridge the gaps when we must, to meet these basic requirements.

We are not yet ready to include compliance requirements for capabilities such as hardware portability, carrier grade performance, fault management and other operational features, security, MANO and VNF verification. These areas are being studied for consideration in future OVP releases.

In some areas, we will start with a limited level of verification initially, constrained by what community resources are able to support at this time, but still serve a basic need that is not being fulfilled elsewhere. In these areas, we bring significant value to the community we serve by starting a new area of verification, breaking new ground and expanding it in the future.

In other areas, the functions being verified have yet to reach wide adoption but are seen as important requirements in NFV, or features are only needed for specific NFV use cases but an industry consensus about the APIs and behaviors is still deemed beneficial. In such cases, we plan to incorporate the test areas as optional. An optional test area will not have to be run or passed in order to achieve compliance. Optional tests provide an opportunity for vendors to demonstrate compliance with specific OPNFV features beyond the mandatory test scope.

5.4.2. Analysis of Scope

In order to define the scope of the 2019.12 release of the compliance and verification program, this section analyzes NFV-focused platform capabilities with respect to the high-level objectives and the general approach outlined in the previous section. The analysis determines which capabilities are suitable for inclusion in this release of the OVP and which capabilities are to be addressed in future releases.

  1. Basic Cloud Capabilities

The intent of these tests is to verify that the SUT has the required capabilities that a basic VNF needs, and these capabilities are implemented in a way that enables this basic VNF to run on any OPNFV compliant deployment.

A basic VNF can be thought of as a single virtual machine that is networked and can perform the simplest network functions, for example, a simple forwarding gateway, or a set of such virtual machines connected only by simple virtual network services. Running such basic VNF leads to a set of common requirements, including:

  • image management (testing Glance API)
  • identity management (testing Keystone Identity API)
  • virtual compute (testing Nova Compute API)
  • virtual storage (testing Cinder API)
  • virtual networks (testing Neutron Network API)
  • forwarding packets through virtual networks in data path
  • filtering packets based on security rules and port security in data path
  • dynamic network runtime operations through the life of a VNF (e.g. attach/detach, enable/disable, read stats)
  • correct behavior after common virtual machine life cycles events (e.g. suspend/resume, reboot, migrate)
  • simple virtual machine resource scheduling on multiple nodes

OPNFV mainly supports OpenStack as the VIM up to the 2019.12 release. The VNFs used in the OVP program, and features in scope for the program which are considered to be basic to all VNFs, require commercial OpenStack distributions to support a common basic level of cloud capabilities, and to be compliant to a common specification for these capabilities. This requirement significantly overlaps with OpenStack community’s Interop working group’s goals, but they are not identical. The OVP runs the OpenStack Refstack-Compute test cases to verify compliance to the basic common API requirements of cloud management functions and VNF (as a VM) management for OPNFV. Additional NFV specific requirements are added in network data path validation, packet filtering by security group rules and port security, life cycle runtime events of virtual networks, multiple networks in a topology, validation of VNF’s functional state after common life-cycle events including reboot, pause, suspense, stop/start and cold migration. In addition, the basic requirement also verifies that the SUT can allocate VNF resources based on simple anti-affinity rules.

The combined test cases help to ensure that these basic operations are always supported by a compliant platform and they adhere to a common standard to enable portability across OPNFV compliant platforms.

  1. NFV specific functional requirements

NFV has functional requirements beyond the basic common cloud capabilities, esp. in the networking area. Examples like BGPVPN, IPv6, SFC may be considered additional NFV requirements beyond general purpose cloud computing. These feature requirements expand beyond common OpenStack (or other VIM) requirements. OPNFV OVP will incorporate test cases to verify compliance in these areas as they become mature. Because these extensions may impose new API demands, maturity and industry adoption is a prerequisite for making them a mandatory requirement for OPNFV compliance. At the time of the 2019.12 release, we have promoted tests of the OpenStack IPv6 API from optional to mandatory while keeping BGPVPN as optional test area. Passing optional tests will not be required to pass OPNFV compliance verification.

BGPVPNs are relevant due to the wide adoption of MPLS/BGP based VPNs in wide area networks, which makes it necessary for data centers hosting VNFs to be able to seamlessly interconnect with such networks. SFC is also an important NFV requirement, however its implementation has not yet been accepted or adopted in the upstream at the time of the 2019.12 release.

  1. High availability

High availability is a common carrier grade requirement. Availability of a platform involves many aspects of the SUT, for example hardware or lower layer system failures or system overloads, and is also highly dependent on configurations. The current OPNFV high availability verification focuses on OpenStack control service failures and resource overloads, and verifies service continuity when the system encounters such failures or resource overloads, and also verifies the system heals after a failure episode within a reasonable time window. These service HA capabilities are commonly adopted in the industry and should be a mandatory requirement.

The current test cases in HA cover the basic area of failure and resource overload conditions for a cloud platform’s service availability, including all of the basic cloud capability services, and basic compute and storage loads, so it is a meaningful first step for OVP. We expect additional high availability scenarios be extended in future releases.

  1. Stress Testing

Resiliency testing involves stressing the SUT and verifying its ability to absorb stress conditions and still provide an acceptable level of service. Resiliency is an important requirement for end-users.

The 2019.12 release of OVP includes a load test which spins up a number of VMs pairs in parallel to assert that the system under test can process the workload spike in a stable and deterministic fashion.

  1. Security

Security is among the top priorities as a carrier grade requirement by the end-users. Some of the basic common functions, including virtual network isolation, security groups, port security and role based access control are already covered as part of the basic cloud capabilities that are verified in OVP. These test cases however do not yet cover the basic required security capabilities expected of an end-user deployment. It is an area that we should address in the near future, to define a common set of requirements and develop test cases for verifying those requirements.

The 2019.12 release includes new test cases which verify that the role-based access control (RBAC) functionality of the VIM is behaving as expected.

Another common requirement is security vulnerability scanning. While the OPNFV security project integrated tools for security vulnerability scanning, this has not been fully analyzed or exercised in 2019.12 release. This area needs further work to identify the required level of security for the purpose of OPNFV in order to be integrated into the OVP. End-user inputs on specific requirements in security is needed.

  1. Service assurance

Service assurance (SA) is a broad area of concern for reliability of the NFVI/VIM and VNFs, and depends upon multiple subsystems of an NFV platform for essential information and control mechanisms. These subsystems include telemetry, fault management (e.g. alarms), performance management, audits, and control mechanisms such as security and configuration policies.

The current 2019.12 release implements some enabling capabilities in NFVI/VIM such as telemetry, policy, and fault management. However, the specification of expected system components, behavior and the test cases to verify them have not yet been adequately developed. We will therefore not be testing this area at this time but defer to future study.

  1. Use case testing

Use-case test cases exercise multiple functional capabilities of a platform in order to realize a larger end-to-end scenario. Such end-to-end use cases do not necessarily add new API requirements to the SUT per se, but exercise aspects of the SUT’s functional capabilities in more complex ways. For instance, they allow for verifying the complex interactions among multiple VNFs and between VNFs and the cloud platform in a more realistic fashion. End-users consider use-case-level testing as a significant tool in verifying OPNFV compliance because it validates design patterns and support for the types of NFVI features that users care about.

There are a lot of projects in OPNFV developing use cases and sample VNFs. The 2019.12 release of OVP features two such use-case tests, spawning and verifying a vIMS and a vEPC, correspondingly.

  1. Additional capabilities

In addition to the capabilities analyzed above, there are further system aspects which are of importance for the OVP. These comprise operational and management aspects such as platform in-place upgrades and platform operational insights such as telemetry and logging. Further aspects include API backward compatibility / micro-versioning, workload migration, multi-site federation and interoperability with workload automation platforms, e.g. ONAP. Finally, efficiency aspects such as the hardware and energy footprint of the platform are worth considering in the OVP.

OPNFV is addressing these items on different levels of details in different projects. However, the contributions developed in these projects are not yet considered widely available in commercial systems in order to include them in the OVP. Hence, these aspects are left for inclusion in future releases of the OVP.

5.4.3. Scope of the 2019.12 release of the OVP

Summarizing the results of the analysis above, the scope of the 2019.12 release of OVP is as follows:

  • Mandatory test scope:
    • functest.vping.userdata
    • functest.vping.ssh
    • functest.tempest.osinterop*
    • functest.tempest.compute
    • functest.tempest.identity_v3
    • functest.tempest.image
    • functest.tempest.network_api
    • functest.tempest.volume
    • functest.tempest.neutron_trunk_ports
    • functest.tempest.ipv6_api
    • functest.security.patrole
    • yardstick.ha.nova_api
    • yardstick.ha.neutron_server
    • yardstick.ha.keystone
    • yardstick.ha.glance_api
    • yardstick.ha.cinder_api
    • yardstick.ha.cpu_load
    • yardstick.ha.disk_load
    • yardstick.ha.haproxy
    • yardstick.ha.rabbitmq
    • yardstick.ha.database
    • bottlenecks.stress.ping
  • Optional test scope:
    • functest.tempest.ipv6_scenario
    • functest.tempest.multi_node_scheduling
    • functest.tempest.network_security
    • functest.tempest.vm_lifecycle
    • functest.tempest.network_scenario
    • functest.tempest.bgpvpn
    • yardstick.ha.neutron_l3_agent
    • yardstick.ha.controller_restart
    • functest.vnf.vims
    • functest.vnf.vepc

* The OPNFV OVP utilizes the same set of test cases as the OpenStack interoperability program OpenStack Powered Compute. Passing the OPNFV OVP does not imply that the SUT is certified according to the OpenStack Powered Compute program. OpenStack Powered Compute is a trademark of the OpenStack foundation and the corresponding certification label can only be awarded by the OpenStack foundation.

Note: The SUT is limited to NFVI and VIM functions. While testing MANO component capabilities is out of scope, certain APIs exposed towards MANO are used by the current OPNFV compliance testing suite. MANO and other operational elements may be part of the test infrastructure; for example used for workload deployment and provisioning.

5.4.4. Scope considerations for future OVP releases

Based on the previous analysis, the following items are outside the scope of the 2019.12 release of OVP but are being considered for inclusion in future releases:

  • service assurance
  • use case testing
  • platform in-place upgrade
  • API backward compatibility / micro-versioning
  • workload migration
  • multi-site federation
  • service function chaining
  • platform operational insights, e.g. telemetry, logging
  • efficiency, e.g. hardware and energy footprint of the platform
  • interoperability with workload automation platforms e.g. ONAP
  • resilience
  • security and vulnerability scanning
  • performance measurements

5.5. Criteria for Awarding Compliance

This section provides guidance on compliance criteria for each test area. The criteria described here are high-level, detailed pass/fail metrics are documented in Dovetail test specifications.

  1. All mandatory test cases must pass.

Exceptions to this rule may be legitimate, e.g. due to imperfect test tools or reasonable circumstances that we can not foresee. These exceptions must be documented and accepted by the reviewers.

  1. Optional test cases are optional to run. Its test results, pass or fail, do not impact compliance.

Applicants who choose to run the optional test cases can include the results of the optional test cases to highlight the additional compliance.

5.6. Exemption from strict API response validation

Vendors of commercial NFVI products may have extended the Nova API to support proprietary add-on features. These additions can cause Nova Tempest API tests to fail due to unexpected data in API responses. In order to resolve this transparently in the context of OVP, a temporary exemption process has been created. More information on the exemption can be found in section Disabling Strict API Validation in Tempest.