Office 365 Tenant to Tenant Migration Step By Step – Secure and Seamless

What are the Benefits of Performing Tenant to Tenant Migration in Office 365?

• Office 365 admins can have easy user management by the consolidation of multiple tenants into one tenant.
• Organizations can save costs by eliminating additional licenses and resources required for multiple o365 tenants.
• With a single Office 365 tenant admins can apply centrally managed policies to improve data security and compliance.
• It is more scalable and reliable and collaborative to utilize a single tenant over multiple.
• Through a single Office 365 tenant you can experience Seamless migration of data and applications with minimal disruption.

But before diving into the possible solutions, let’s have a quick glance at the user’s query to understand the whole scenario in a better way.

User Query:

Scenario:

Nowadays, organizations are rapidly adopting Office 365, and the increasing number of Mergers, Acquisitions, and Divestiture activities, leaves organizations dealing with various types of data migration projects in Office 365.

Here comes the key part of this blog, there are mainly two ways to carry out data migration in O365. The first is the manual method using the PowerShell Scripts and the second is the automated solution. Let’s dive into each approach to perform this operation step by step.

Pre-Requisites You Need to Follow As Office 365 Tenant to Tenant Migration Checklist

These are the below checklists or migration plans for users to perform this operation safely without facing any issues or challenges.

1. Domain Preparation

Domain setup entails the following measures:

1. Check that you have enough Microsoft 365 licenses.
2. To facilitate the transfer, create admin accounts in both the source and target systems.
3. Add new mailboxes, room/resource mailboxes, and distribution groups to the destination.
4. To execute AD DS consolidation, use AD DS tools and, if necessary, manually or automatically synchronize the source and target domains.
5. After the migration, teach your end-users how to use Microsoft 365.

2. Domain validation

1. Begin by entering and verifying the target tenant domain into Microsoft 365.
2. Configure DNS TXT records and connect a source domain to the target Microsoft 365 admin center.
3. Check that the domain is only being utilized by one tenant. The verification will fail if this condition is not met.

Following the completion of these processes, it will take approximately 72 hours for the change to become visible.

3. Migration Planning

1. Create a list of the user mailboxes that you want to migrate, as well as a CSV file for mapping.
2. Make a note of the lowest TTL value in the MX record (of the primary email domain).
3. To prevent changes to the source tenant’s AD DS account from being synchronized to the Microsoft 365 platform, disable directory sync for the origin tenancy (through the Microsoft 365 admin center). The deactivation procedure may take up to several hours.

The Stage Of Tenant-to-Tenant Migration in O365

1. Put a halt to the influx of mail.

To prevent incoming mail flow to the originating tenant, change the primary MS record to an unreachable value or utilize a third-party solution. You can simply plan the time for this step since you entered the lowest TTL value on the MX record (of the primary email domain) during the preparation process.

2. Source preparation before Office 365 tenant to tenant migration.

The primary mail domain must be deleted from all items in the original tenancy before transferring the Office 365 mailbox to some other tenant.

• Reset your default email address to the one connected with your Microsoft 365 account.
• Using the Lync Admin Portal, delete all Lync licenses from the source tenant.
• Restore the prior domain’s default email address for distribution lists, rooms, and resources.
• All tenant objects’ secondary email addresses should be removed.
• Type Get-MsolUser -DomainName xyz.com in Windows PowerShell to discover any objects that are still utilizing the main email address or are resisting deletion.

3. Preparing the target Domain before tenant-to-tenant migration in O365

• Set the auto-discover CNAME.
• You must build a new domain in the target tenancy when using AD FS.
• Activate and license new user accounts in the target domain.
• Make the principal email address of the originating domain the primary email address for new users (done using Windows PowerShell). Choose how to transmit passwords to end-users.
• Once the user mailboxes are active, modify the mail routing and point the MX record to the new Office 365 email address.

Examine the mail flow into and out of the specific tenant.

If The Migration Being Done is For Less Than 500 Users

If the number of users is less than 500, users can utilize the manual approach. There might be a cutoff date to assist in restricting the amount of data transferred. You may choose a time frame, say six months, for transferring mail, calendar data, and contact information.

In this scenario, which manual technique can be used?

PowerShell is a Microsoft idea that consists of a command-line shell and a scripting language for automating activities. This method is tough for non-technical individuals to grasp.

Why You Should Not Use the Manual Method for Tenant-to-Tenant Migration in O365?

In this manual method, users need to run PowerShell cmdlets scripts, which require great technical expertise. A minor mistake or mis-stype in these scripts can result in multiple errors and failures in this migration process. Moreover, PowerShell has its limitations as it does not maintain data integrity and folder structure or hierarchy.

• The Complexity of the Process: As it is a manual process, hence you have to proceed with every step by yourself. Moreover, this process involves multiple technical steps, including configuring and connecting to the source and destination tenants. Additionally, selecting the data to be migrated, and managing the entire migration process. This can be a complex process, particularly for large amounts of data or for organizations with multiple users and complex data structures.
• The Inefficiency of the Process: The manual migration process is often slow and can take a significant amount of time to complete particularly when performing a large-scale data migration. Moreover, it can hamper the running of the business by creating a temporary communication halt. Which later can cause disruptions to business operations and lead to productivity losses.
• The Risk of Organizational Data Loss: Manually performing tenant-to-tenant migration in O365 carries a risk of data loss due to human error or the inability to technical implementation. This could result in improper migration, leading to data loss and potential business continuity issues.
• Difficulty in Handling Permissions: It becomes extremely complex to handle user and other resources’ permissions while manually performing Office 365 tenant-to-tenant migration. Because at the post-migration stage, it’s harder to keep track of who has access to what and where. This can eventually lead to security vulnerabilities and compliance issues.
• Complexity in Handling Custom Applications: This process becomes completely worthless when an organization is using custom applications or solutions that integrate with Office 365. This is because there are chances that custom applications and solutions may not work properly in the new tenant environment, leading to additional complications and business downtime.

Concluding Words

Performing Office 365 tenant migration can be a tedious and laborious task, moreover, users should be technically sound to do the same. Understanding the complications faced by users, we have provided the most convenient solution for this operation.

Using the above-mentioned tool, users without having any prior technical knowledge can also easily perform O365 migration projects, while keeping data integrity and security. Therefore we have discussed Office 365 tenant-to-tenant migration step by step.