Exchange Server administrators need to choose a migration strategy to successfully migrate the data from on-premises Exchange Server to Office 365 (Microsoft 365). This would involve planning, decision, and execution to ensure a smooth migration with no data or business loss. The decision is taken depending on the technical aspect, business, licensing, and compliance requirements. All this depends on the structure of the company and the business effort for the migration. In this article, we will explain how an experienced Exchange admin should choose a migration strategy under real constraints. We will also be talking about using third-party Exchange migration tool for migrating the data to ensure a smooth and seamless migration.
Things to Consider when Choosing a Migration Strategy
Here are some things you should consider when deciding upon a strategy for on-premises Exchange to Microsoft 365 migration.
Constraints of the Current Environment
An experienced administrator should start from this part. They should first map the constraints before jumping to the migration method. So, see the feasibility and plan for such a migration to ensure zero-downtime and peace of mind that all the data would be migrated. Also, check the network recommendations, which would be beneficial for the migration, unsupported systems, and legal compliance and other regulations that the business would have for the migration. After this and a full assessment of the infrastructure, they can evaluate the information and decide a migration method, depending on the efforts needed.
Evaluation of the Current Infrastructure
Before choosing the migration method, an Exchange admin should confirm if the current setup is suitable for the hybrid model. They should check the version of Exchange Server installed and the supported Cumulative Update. The Autodiscover service, along with EWS, MRS, and OAuth, must be in a working condition with the respective authorized public certificates installed. The Active Directory must be clean from any extra attributes that could break the hybrid setup. Also make sure that there are:
- No duplicate proxy addresses.
- No orphaned or stale objects.
- No domains which would not be migrated.
- No illegal characters in user information or details.
If any of the above mentioned is not in place, the hybrid method will not work. In this case, opt for a different method.
Choosing the Right Migration Method
When choosing the migration method, an Exchange admin needs to keep in mind the downtime, resources required, existing environment, and various other aspects. They can choose from the following two native migration methods, depending on the requirements.
Cutover Migration
Cutover migration is suitable when the company has to move everything to Office 365 at once. This method works for small organizations having 20 to 50 users.
One would need to take into account that this method requires downtime as there is sudden changeover with no coexistence. Also, there is no option for public folder migration. As soon as the changeover is done, one would need to re-configure the Microsoft Outlook profile on each and every user to point it to the Office 365.
This method is mostly used when the hybrid method is not possible due to budget or infrastructure constraints. On the other hand, this would be ideal for small setups and limited resources.
Hybrid Migration
If the environment supports the hybrid migration model, this migration method is the most commonly suggested. This method allows seamless coexistence between the local server and the cloud and both act as one Exchange Server with SMTP coexistence. One can granularly move the mailboxes from one side to another. It can offer long-term hybrid setup, if needed. It is also a very convenient method to reduce user support as the Microsoft Outlook profile will be changed automatically when the mailbox of the user has been completely moved to the cloud.
This might sound good, but one should also consider the cons of the method. It is a complex setup and restrictions on the network, misconfiguration of the Exchange Server, connectors, certificate issues, and other factors can delay the project and hinder the migration. Moreover, if the project needs to be done fast, the hybrid migration method will not be suitable. Although it is one of the most seamless methods, it is also the slowest.
Make Third-Party Exchange Migration Tools Part of your Strategy
Third-party Exchange migration tools come with various features and functionalities to ease and speed up the migration of data. Stellar Migrator for Exchange is one such tool can help with the migration of data. This tool can migrate user mailboxes, archives, public folders, and shared mailboxes from on-premises Exchange to Office 365 with granular migration, delta (incremental) migration, and automatic mailbox matching. It supports multi-forest Exchange Server deployments.
The tool will help in overcoming the challenges that one might face when it comes to the complexity of setup, the Exchange Server or network (not up to the standard), and the infrastructure (does not support hybrid). This tool provides the flexibility and helps reduce the migration complexity and risk.
Conclusion
As we have seen above, there are a lot of things that one would consider when having a full migration from local Exchange Server to Office 365. An experienced administrator has the responsibility to plan and choose the right migration method in order to have a seamless and smooth migration while ensuring that there is no data loss. Therefore, one must have reliable and robust Exchange migration tool, such as Stellar Migrator for Exchange, in hand that can help in migrating data from local server to cloud without any hassle and data loss.
