Guide to Microsoft Entra ID application identity migration

If your organization still relies on legacy identity systems, you know the struggle is real. 

Security vulnerabilities, compatibility headaches, and increasing maintenance costs make it clear: it’s time to modernize. There are several options, and Microsoft Entra ID (formerly Azure Active Directory) is a widely adopted cloud identity platform with over 50% over the market share offering a secure, scalable, and integrated approach to identity management. 

But where do you start? Migration can be quite a daunting process, with risks of downtime, security gaps, and complex application dependencies. 

This guide walks you through a structured, expert-backed approach to AD migration, helping you avoid common pitfalls and successfully transition your identity infrastructure.

But first, some statistics. 

Apps on legacy IDPs are incompatible with modern identity systems

According to the 2025 State of Multi-cloud Report, 75% of enterprises use two or more identity providers (IDPs), and 11% use five or more IDPs. They are also having to manage a hybrid state of on-prem and multi-cloud.

Most of the enterprise organizations surveyed have not been able to get the majority of their workloads off legacy, on-premises identity systems to the cloud, and very few believe they will ever be able fully to move to the cloud. 

The harsh reality for many enterprises is the consistent struggle with identity modernization barriers like source code and resourcing, with 78% of respondents still facing those hurdles. Why? Because moving apps and identities is hard — since old, on-premises systems aren’t built for modern cloud systems. 

Traditionally, before an app could be moved, the code needed to be rewritten to be compatible with a cloud system. For some apps, it simply isn’t possible to recode.

What are the common challenges in AD migration?

Moving to Microsoft Entra ID is a significant business mindset shift — it reshapes how identity management is handled across your organization. A key issue is that organizations often underestimate the complexity of application identity migration, leading to disruptions that can frustrate users and open security loopholes.

Here are four of the most common problems.

• Application compatibility issues: Many legacy applications aren’t designed to work with modern authentication methods like SAML, OAuth, or OpenID Connect.
• Security vulnerabilities: Poorly planned migrations can lead to unauthorized access, misconfigurations, and compliance risks.
• Data integrity concerns: Ensuring every user account, permission, and access control policy migrates correctly is critical.
• Potential downtime: If authentication breaks, business operations can grind to a halt.

The good news? With a well-structured migration strategy, these challenges are entirely manageable. Let’s take a closer look at how one common legacy IDP, SiteMinder, compares to Microsoft Entra ID and why many organizations are making the switch.

SiteMinder vs. Microsoft Entra ID: Key differences

As organizations evaluate their options, one question often arises: Should we migrate from SiteMinder to Microsoft Entra ID? 

Understanding the differences between these platforms can go a long way in making an informed decision.

The case for app identity migration

Legacy systems like SiteMinder were essentially built for a different IT environment where most applications were on-premises. But today’s hybrid and cloud-first environments demand modern identity solutions. If your organization is looking for seamless integration, enhanced security, and better user experiences, moving to Active Directory or Entra ID is the logical next step.

A step-by-step migration checklist to Microsoft Entra ID

Migrating your identity systems requires careful planning. Without a structured approach, you could face security risks, data loss, and prolonged downtime. 

Identity orchestration is a new approach that automates the modernization of applications and users in the cloud.

Identity orchestration software automates much of the process and enables enterprises to move off your legacy IDP without rewriting your applications’ code. 

Here’s a proven, step-by-step framework to guide you through the process.

Step 1: Assess your current identity environment

Your migration journey starts with understanding your existing setup. Conduct a thorough inventory of user identities, applications, and authentication protocols.

• Identify all on-premises identity sources and how they interact with applications.
• Determine which legacy authentication methods need modernization.
• Assess compliance requirements and map out security risks.

You can use Strata’s Maverics Platform to look at the data inside of IDPs like SiteMinder, OAP and Ping Federate.

Think of Maverics like an x-ray for your legacy IDP environment. It connects, then discovers how your applications are configured and determines which ones could be risky or complex migrations.

Maverics also gives you the information to catalog your identity structures. From your servers to your agents, you’ll know how your environment looks so that you can plan a deliberate and predictable migration.

Step 2: Plan your migration strategy

A migration shouldn’t be an initiative you rush into. Strategizing upfront reduces errors and minimizes disruptions.

• Choose your migration method: Big bang, phased migration, or hybrid co-existence.
• Set clear milestones and create a pilot migration to test everything first.
• Establish backup and rollback plans—never assume things will go perfectly.

Proper planning makes the actual migration much smoother — it’s the difference between chaos and control.

Step 3: Migrate users and groups

User migration is a critical phase since errors can lock people out or weaken security.

• Synchronize user identities using the IDP’s services or Identity Orchestration tools.
• Implement multi-factor authentication (MFA) and enforce Zero Trust principles.
• Test authentication processes before rolling out the migration at scale.

This part of the process gives you the opportunity to harden your user accounts, like adding 2-step verification or multi-factor authentication (MFA) to protect them better off-premises.

If users can’t log in, they’ll call IT — and they won’t be happy. Testing prevents frustration and ensures a smooth transition.

Step 4: Migrate applications

Applications often present the biggest challenge in identity migrations. Many rely on outdated authentication methods that don’t work with modern IDPs.

• Use Identity Orchestration tools to enable cloud-based authentication without rewriting code.
• Configure applications for modern authentication protocols (SAML, OAuth, OpenID Connect).
• Test application authentication workflows and resolve issues before they’re fully deployed.

You can run Maverics on the edge of the enterprise, where the identities can live with the identity provider. Users sign into the identity provider, which connects to Maverics. Maverics then passes the session into the application and ties into the coexistence of SiteMinder.

During this step, Maverics extends multi-factor authentication to your applications without any rewriting.

Step 5: Optimize, monitor, and decommission legacy systems

Once everything is migrated, your job isn’t quite done. You need to monitor and optimize your new Entra ID setup.

• Set up real-time monitoring and alerting for potential authentication failures.
• Conduct post-migration security audits to ensure proper configurations.
• Gradually phase out and decommission legacy systems, reducing costs and attack surfaces.

With the right approach, your migration will be a transformation, not a disruption.

Quick overview of best practices for a smooth migration

A successful migration doesn’t happen by accident — it requires careful planning, the right tools, and a strategic approach. 

To make your cloud migration faster, safer, and more effective, keep these best practices in mind:

• Automate as much as possible. Use tools like Strata’s Maverics and Microsoft’s connector tools to streamline identity synchronization.
• Adopt a Zero Trust approach. Apply least privilege access and enable continuous authentication.
• Ensure application backward compatibility. Use identity federation tools where needed.
• Have a rollback strategy. If something breaks, be ready to revert quickly.
• Educate your stakeholders. Train IT teams and end-users on new authentication workflows.

Note that any missteps can lead to security vulnerabilities, performance issues, and frustrated users. By following industry best practices, organizations can ensure a seamless transition while minimizing risks.

Ready to migrate to Microsoft Entra ID?

An Identity Orchestration platform lets you speed up the process of moving applications and identity from on-premises identity systems by eliminating the need to rewrite apps. It runs IDPs like SiteMinder simultaneously with cloud identity from a modern identity provider as long as you need to run both systems. Then, when you’re ready, you can retire your legacy system and enjoy the benefits of the modern cloud world.

Strata’s Maverics Identity Orchestration platform makes AD migration frictionless by enabling seamless authentication across modern and legacy applications without rewriting code. Find out how to modernize your your application identities at scale in this blog post.