Upgrade to v2

Azure Machine Learning's v2 REST APIs, Azure CLI extension, and Python SDK introduce consistency and a set of new features to accelerate the production machine learning lifecycle. This article provides an overview of upgrading to v2 with recommendations to help you decide on v1, v2, or both.

Prerequisites

• General familiarity with Azure Machine Learning and the v1 Python SDK.
• Understand what is v2?

Should I use v2?

You should use v2 if you're starting a new machine learning project or workflow. You should use v2 if you want to use the new features offered in v2. The features include:

• Managed Inferencing
• Reusable components in pipelines
• Improved scheduling of pipelines
• Responsible AI dashboard
• Registry of assets

A new v2 project can reuse existing v1 resources like workspaces and compute and existing assets like models and environments created using v1.

Some feature gaps in v2 include:

• Spark support in jobs - this is currently in preview in v2.
• Publishing jobs (pipelines in v1) as endpoints. You can however, schedule pipelines without publishing.
• Support for SQL/database datastores.
• Ability to use classic prebuilt components in the designer with v2.

You should then ensure the features you need in v2 meet your organization's requirements, such as being generally available.

Which v2 API should I use?

In v2 interfaces via REST API, CLI, and Python SDK are available. The interface you should use depends on your scenario and preferences.

API	Notes
REST	Fewest dependencies and overhead. Use for building applications on Azure Machine Learning as a platform, directly in programming languages without an SDK provided, or per personal preference.
CLI	Recommended for automation with CI/CD or per personal preference. Allows quick iteration with YAML files and straightforward separation between Azure Machine Learning and ML model code.
Python SDK	Recommended for complicated scripting (for example, programmatically generating large pipeline jobs) or per personal preference. Allows quick iteration with YAML files or development solely in Python.

Mapping of Python SDK v1 to v2

See each of the following articles for a comparison code mapping for SDK v1 vs v2.

Resources and assets	Article
Workspace	Workspace management in SDK v1 and SDK v2
Datastore	Datastore management in SDK v1 and SDK v2
Data	Data assets in SDK v1 and v2
Compute	Compute management in SDK v1 and SDK v2
Training	Run a script
Training	Local runs
Training	Hyperparameter tuning
Training	Parallel Run
Training	Pipelines
Training	AutoML
Models	Model management in SDK v1 and SDK v2
Deployment	Upgrade deployment endpoints to SDK v2

Resources and assets in v1 and v2

This section gives an overview of specific resources and assets in Azure Machine Learning. See the concept article for each entity for details on their usage in v2.

Workspace

Workspaces don't need to be upgraded with v2. You can use the same workspace, regardless of whether you're using v1 or v2.

If you create workspaces using automation, do consider upgrading the code for creating a workspace to v2. Typically Azure resources are managed via Azure Resource Manager (and Bicep) or similar resource provisioning tools. Alternatively, you can use the CLI (v2) and YAML files.

For a comparison of SDK v1 and v2 code, see Workspace management in SDK v1 and SDK v2.

Connection (workspace connection in v1)

Workspace connections from v1 are persisted on the workspace, and fully available with v2.

For a comparison of SDK v1 and v2 code, see Workspace management in SDK v1 and SDK v2.

Datastore

Object storage datastore types created with v1 are fully available for use in v2. Database datastores are not supported; export to object storage (usually Azure Blob) is the recommended migration path.

For a comparison of SDK v1 and v2 code, see Datastore management in SDK v1 and SDK v2.

Data (datasets in v1)

Datasets are renamed to data assets. Backwards compatibility is provided, which means you can use V1 Datasets in V2. When you consume a V1 Dataset in a V2 job you will notice they are automatically mapped into V2 types as follows:

• V1 FileDataset = V2 Folder (uri_folder)
• V1 TabularDataset = V2 Table (mltable)

It should be noted that forwards compatibility is not provided, which means you cannot use V2 data assets in V1.

This article talks more about handling data in v2 - Read and write data in a job

For a comparison of SDK v1 and v2 code, see Data assets in SDK v1 and v2.

Compute

Compute of type AmlCompute and ComputeInstance are fully available for use in v2.

For a comparison of SDK v1 and v2 code, see Compute management in SDK v1 and SDK v2.

Jobs (experiments, runs, pipelines in v1)

In v2, "experiments", "runs", and "pipelines" are consolidated into jobs. A job has a type. Most jobs are command jobs that run a command, like python main.py. What runs in a job is agnostic to any programming language, so you can run bash scripts, invoke python interpreters, run a bunch of curl commands, or anything else. Another common type of job is pipeline, which defines child jobs that may have input/output relationships, forming a directed acyclic graph (DAG).

For a comparison of SDK v1 and v2 code, see

• Run a script
• Local runs
• Hyperparameter tuning
• Parallel Run
• Pipelines
• AutoML

Designer

You can use designer to build pipelines using your own v2 custom components and the new prebuilt components from registry. In this situation, you can use v1 or v2 data assets in your pipeline.

You can continue to use designer to build pipelines using classic prebuilt components and v1 dataset types (tabular, file). You cannot use existing designer classic prebuilt components with v2 data asset.

You cannot build a pipeline using both existing designer classic prebuilt components and v2 custom components.

Model

Models created from v1 can be used in v2.

For a comparison of SDK v1 and v2 code, see Model management in SDK v1 and SDK v2

Endpoint and deployment (endpoint and web service in v1)

With SDK/CLI v1, you can deploy models on ACI or AKS as web services. Your existing v1 model deployments and web services will continue to function as they are, but Using SDK/CLI v1 to deploy models on ACI or AKS as web services is now considered as legacy. For new model deployments, we recommend upgrading to v2. In v2, we offer managed endpoints or Kubernetes endpoints. The following table guides our recommendation:

Endpoint type in v2	Upgrade from	Notes
Local	ACI	Quick test of model deployment locally; not for production.
Managed online endpoint	ACI, AKS	Enterprise-grade managed model deployment infrastructure with near real-time responses and massive scaling for production.
Managed batch endpoint	ParallelRunStep in a pipeline for batch scoring	Enterprise-grade managed model deployment infrastructure with massively parallel batch processing for production.
Azure Kubernetes Service (AKS)	ACI, AKS	Manage your own AKS cluster(s) for model deployment, giving flexibility and granular control at the cost of IT overhead.
Azure Arc Kubernetes	N/A	Manage your own Kubernetes cluster(s) in other clouds or on-premises, giving flexibility and granular control at the cost of IT overhead.

For a comparison of SDK v1 and v2 code, see Upgrade deployment endpoints to SDK v2. For migration steps from your existing ACI web services to managed online endpoints, see our upgrade guide article and blog.

Environment

Environments created from v1 can be used in v2. In v2, environments have new features like creation from a local Docker context.

Managing secrets

The management of Key Vault secrets differs significantly in V2 compared to V1. The V1 set_secret and get_secret SDK methods are not available in V2. Instead, direct access using Key Vault client libraries should be used. When accessing secrets from a training script, you can use either the managed identity of the compute or your identity.

For details about Key Vault, see Use authentication credential secrets in Azure Machine Learning training jobs.

Scenarios across the machine learning lifecycle

There are a few scenarios that are common across the machine learning lifecycle using Azure Machine Learning. We'll look at a few and give general recommendations for upgrading to v2.

Azure setup

Azure recommends Azure Resource Manager templates (often via Bicep for ease of use) to create resources. The same is a good approach for creating Azure Machine Learning resources as well.

If your team is only using Azure Machine Learning, you may consider provisioning the workspace and any other resources via YAML files and CLI instead.

Prototyping models

We recommend v2 for prototyping models. You may consider using the CLI for an interactive use of Azure Machine Learning, while your model training code is Python or any other programming language. Alternatively, you may adopt a full-stack approach with Python solely using the Azure Machine Learning SDK or a mixed approach with the Azure Machine Learning Python SDK and YAML files.

Production model training

We recommend v2 for production model training. Jobs consolidate the terminology and provide a set of consistency that allows for easier transition between types (for example, command to sweep) and a GitOps-friendly process for serializing jobs into YAML files.

With v2, you should separate your machine learning code from the control plane code. This separation allows for easier iteration and allows for easier transition between local and cloud. We also recommend using MLflow for tracking and model logging. See the MLflow concept article for details.

Production model deployment

We recommend v2 for production model deployment. Managed endpoints abstract the IT overhead and provide a performant solution for deploying and scoring models, both for online (near real-time) and batch (massively parallel) scenarios.

Kubernetes deployments are supported in v2 through AKS, enabling Azure cloud and on-premises deployments managed by your organization.

Machine learning operations (MLOps)

A MLOps workflow typically involves CI/CD through an external tool. Typically a CLI is used in CI/CD, though you can alternatively invoke Python or directly use REST.

The solution accelerator for MLOps with v2 is being developed at https://github.com/Azure/mlops-v2 and can be used as reference or adopted for setup and automation of the machine learning lifecycle.

A note on GitOps with v2

A key paradigm with v2 is serializing machine learning entities as YAML files for source control with git, enabling better GitOps approaches than were possible with v1. For instance, you could enforce policy by which only a service principal used in CI/CD pipelines can create/update/delete some or all entities, ensuring changes go through a governed process like pull requests with required reviewers. Since the files in source control are YAML, they're easy to diff and track changes over time. You and your team may consider shifting to this paradigm as you upgrade to v2.

You can obtain a YAML representation of any entity with the CLI via az ml <entity> show --output yaml. Note that this output will have system-generated properties, which can be ignored or deleted.

Should I upgrade existing v1 code to v2

You can reuse your existing v1 assets in your v2 workflows. For instance a model created in v1 can be used to perform Managed Inferencing in v2.

Optionally, if you want to upgrade specific parts of your existing v1 code to v2, please refer to the comparison links provided in this document.

Can I use v1 and v2 together?

v1 and v2 can co-exist in a workspace. You can reuse your existing assets in your v2 workflows. For instance a model created in v1 can be used to perform Managed Inferencing in v2. Resources like workspace, compute, and datastore work across v1 and v2, with exceptions. A user can call the v1 Python SDK to change a workspace's description, then using the v2 CLI extension change it again. Jobs (experiments/runs/pipelines in v1) can be submitted to the same workspace from the v1 or v2 Python SDK. A workspace can have both v1 and v2 model deployment endpoints.

Using v1 and v2 code together

We do not recommend using the v1 and v2 SDKs together in the same code. It is technically possible to use v1 and v2 in the same code because they use different Azure namespaces. However, there are many classes with the same name across these namespaces (like Workspace, Model) which can cause confusion and make code readability and debuggability challenging.

Next steps

• Get started with the CLI (v2)
• Get started with the Python SDK (v2)