Essential insights for IT admins: What to know before a tenant-to-tenant migration

A tenant-to-tenant migration takes a fair amount of preparation but with a good plan in place, you'll get through it with flying colors. These quick tips and insights will help make the process as smooth as possible and ensure your migration is a success!

A tenant-to-tenant migration is just that: a process that lets you move data from one Microsoft 365 tenant to another. It's like moving houses, but instead of physical things, it's moving data. It comes in handy especially when you're switching from one cloud provider (like a Microsoft 365 tenant) to another. It might sound tricky, but with a little bit of planning and know-how, it can be done seamlessly and without interrupting your business operations.

When you're thinking about doing a tenant-to-tenant migration, it's important to remember that it takes a fair amount of preparation. Just like planning a move, it might take some time and effort, but with a good plan in place, you'll be able to get through it with flying colors.

Some things to keep in mind include understanding what you need from your source tenant, figuring out what your target tenant (also destination tenant) should look like, and making sure everything is in the right place when you're finished with your migration project.

Understanding tenant migration

Tenant migration is the process of transferring users, resources, and data from one Microsoft 365 (M365) tenant to another. This process is often necessary in scenarios such as mergers and acquisitions, divestitures, organizational changes, compliance and governance requirements, and cost savings. Understanding the complexities of tenant migration is crucial to ensure a successful migration with minimal disruption to users.

What to consider in a tenant-to-tenant migration?

There are different reasons why you’ll want to go through a tenant-to-tenant migration process. In short, they have to do with structural changes in your business or organization. Also, there are different approaches you can take. Let's take a look at what they are.

Thankfully, here are 2 easy ways to migrate Microsoft Teams from one tenant to another.

Scenarios

• ‍Business mergers—When two separate businesses combine into a single new one.
• Business acquisitions—When one business fully absorbs another through a purchase: in most cases, it results in the liquidation of the acquired business.
• Divestitures—When a business unit ceases to exist after a purchase or a restructuring.
• Reorganizations—When you move business units, such as from one region to another, or decommission a tenant.

Types of tenant-to-tenant migrations

Two basic types of tenant-to-tenant migrations will suit the vast majority of cases:

1. Phased tenant-to-tenant migration:

• Data migration process is gradual
• Suits tenant-to-tenant migrations of any scale
• Users assume new domains in the target tenant
• Domains are not transferred from the source tenant
• Lower risk, longer timeline

2. Single-event tenant-to-tenant migration:

• Data migration happens in one event
• Higher risk, shorter timeline
• Suits migrations below 15,000 users and/or 7 TB of site content

If you're looking to perform any of these migrations, try ShareGate's tenant-to-tenant migration tool for merging your environments.

Single or multiple tenants? Which process suits your needs?

In a tenant-to-tenant migration process, you have the option of moving your data from your source tenant into one single target tenant or into multiple tenants. Let’s see the benefits and limitations of each case.

For a single tenant

This is the most common approach and the best option for most organizations. This approach makes it easy for your team to collaborate across all Microsoft 365 apps and services. With everyone under one roof, your users can communicate and share resources seamlessly, enhancing productivity and teamwork. A single-tenant migration also means IT will have a simpler job securing the target tenant.

For multiple tenants

This approach is recommended for organizations with many departments, sister companies, different geographic locations, and global end users—meaning that the business would have to comply with various data protection legislations and deal with different license providers.

However, it’s important to consider that collaboration across multiple tenants can be more challenging. Users from one tenant will have to be guests from the other. This guest access can complicate security management by introducing additional vulnerabilities, making it more difficult for IT teams to ensure robust protections across multiple Microsoft 365 tenants.

The good news is that any migration project doesn't have to be daunting! ShareGate's Microsoft 365 migration checklist simplifies the process, providing step-by-step guidance to guarantee a successful migration journey.

As your company evolves, you may find yourself facing more complex migration scenarios, particularly when managing multiple tenants simultaneously or large tenants with petabytes of data. In these situations, a one-by-one approach might not be enough to keep things running smoothly.  

That’s where concurrent migrations come into play. By handling multiple migrations simultaneously, you can streamline the process and reduce downtime, even in the most challenging circumstances. Let’s explore how you can make concurrent migrations work for you.

Concurrent migrations

Concurrent migrations run multiple migrations simultaneously on different workspaces, creating a bigger pipe for data to flow through at once. If one migration stalls, the others continue uninterrupted. This strategy can reduce the overall time needed for migration, which is especially valuable in complex scenarios involving multiple business units or departments. Concurrent migration enhances efficiency—getting everything done faster without sacrificing quality and security.

Helpful tips for a successful concurrent migration

To make concurrent migrations work for you, consider these best practices:

• Automate where you can: Use migration tools that support automation to handle most of the workload. This helps prevent mistakes and speeds up the process.
• Stagger migration windows: Don’t start all migrations at once Instead, spread them out to reduce strain on your network and servers.
• Monitor everything closely: Keep a close eye on each migration’s progress. Set up alerts to catch problems early before they become major problems.
• Assign machines to different target spaces: If you move content from multiple machines to the same space within your destination, like the same library or site, it can create errors and slow down the process. That’s because the Azure queues created by your migration tasks are more likely to find conflicts if everything is flowing into the same space.
• Communicate and report: Clear communication and reporting among the migration team are crucial. Concurrent migrations aim for speed but require careful planning to avoid conflicts and issues. Watch out for dependencies and overlap!

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3 best practices for tenant-to-tenant migrations

Tenant-to-tenant migrations can be complex, so here are a few best practices that will come in handy if you need to perform one.

Understand your migration process

We can’t stress this enough: Having a well-thought-out strategy is vital for a successful tenant-to-tenant migration process. Of course, there’s a plethora of elements to consider in your planning, and no two organizations will have the exact same needs. However, here are a few ideas that can help any IT team get started before a tenant-to-tenant migration process:

• Assess the risks, such as data loss (if the data is not backed up or transferred properly), downtime affecting productivity, and complexity—resulting in difficult collaboration and higher costs.
• Evaluate the opportunities this migration will bring, such as modernizing your content structure and lowering licensing and storage costs.
• Future-proof your future tenant or tenants, limiting the exposure to instabilities down the line and changes in technology and in the business landscape.
• Anticipate the governance policies for the new environment and start designing the guardrails you’ll create to ensure users comply with them.

Fix permissions issues at the source

When it comes to tenant-to-tenant migrations, we like to take the motto “security first” as literally as possible. Since external sharing and permissions are critical aspects of your Microsoft 365 security, you can’t wait to fix any issues in the post-migration. Address these problems in the source tenant before you migrate instead of bringing them over to your new target tenant or tenants.

Clean up your source environment and prepare your target tenant

This could be done either before or after the migration process, but in either case, a tenant-to-tenant migration is a perfect opportunity to rebuild your Microsoft 365 environments. When you declutter and reorganize your SharePoint and make it easier for people to work with Teams, you’ll see adoption rise. Why? Because you’ll be making people happier.

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