Are you willing to migrate data to Office 365? Must read this first.

Hi there

After a couple file server to cloud migration projects I decided to write this article to help you to think about the main points to be considered before migrating data (legacy data, backup, personal folders, home folder, shared folders, departmental folder, etc.) to OneDrive and / or SharePoint Online.

Here are the basic steps before migrating your company to Cloud-based services and applications

Assessment: This step will consume most of the hours in your project once you need to identify which data is about to be migrated, its location (shared folder, DFS structure, etc.) as well as its file system, data size, current permission (users and groups accesses) as well as any remediation you might need to do that’s gonna be part of the Pilot.
In scope and Out of scope definition: At this phase it’s defined what is covered and not by the Consulting Team, Vendor and based on the Client Request as well as with the Assessment Report and the remediation plan on hands. As a Consultant working on a Microsoft Partner we do not recommend or implement any unsupported solution “workaround” to give users the same previous experience. Migrating to OneDrive for Business and / or to SharePoint Online requires a lot of work and some users are really reactive to changes or most of them. However, with a great communication plan in-place, training and piloting an project can be delivered successfully.
Security: This portion needs total attention regarding to move files as well as introducing new tools to access you data from anywhere and all Security features and tools offered by Office 365, Azure and its partners should be considered once their affect your licensing model and pricing. Some features will be only available on different subscriptions and licences types.
Pilot: At this phase one full shared folder or departmental folder needs to be its objective and the migration plan for this folder needs to be assessed, inventoried, backed up and migrated over fulfilling all prerequisites for this project regarding to on-premises to SharePoint Online migration and for the OneDrive for Business user’s private or home folder it is needed a few users to be migrated over and have their OneDrive for Business client deployed and synced over to evaluate user’s experience when handling with this new technology. Here the tools mentioned on this article will be tested and then you might consider to use or not any third party application tool to have this migration done (license costs should affect your project budget).
Communication Plan: For this specific phase of the project be sure to follow or have Microsoft engaged on any Partner Service available such as Fast Track. Please check the OneDrive guide for Enterprise here and for SharePoint Online here. Have always in mind end-user experience when you’re creating any migration campaign and documentation preparation and distribution.
Pilot review: At this phase you have finished the Pilot and tested your communication Plan Effectiveness and might need to evaluate to make any changes to your initial plan from any insights coming from end-users, IT tech staff or any Stakeholders and then make the appropriate changes in-scope and out-of-scope as well as on documentation, communication plans and tools used to accomplish the project. Document everything and report everything to the technical and decision-making personal to make sure your migration CAB (Change advisory-board) submissions will be well handled and approved before you reach the Migration. This is your go/no go decision moment in this project. Moreover, have in mind a quick analysis to each on-premises servers running any folder and files to be migrated looking for any third-party application such as AV or Endpoint that might be causing delays, errors and slowness when doing assessment and piloting stage.
Pre-migration: at this step your you can skip this one and add as a Migration step a full backup of the environment (file servers, shared folders, home folder structure) before you hit the gun. Be ready to disseminate train to trainer program depending on your company size as well as FAQs sessions targeting users by department, locations on their language as well as promoting reminder during each migration phase that you already had defined at the Pilot when you had the change to evaluate technology, users’ needs, training and communication planning.
Migration: Finally you have reached the most expected phase on this project. Be sure you have fixed everything covered during the pilot. Have a full checklist with pass and fail model to make sure all previous steps were completed and are proper configured such as Users sync, licensing, permissions and data to be migrated. A roll-back plan should be in-place, reviewed and approved by CAB even after the pilot (for the pilot itself). The Microsoft tools offered are able to re-run a differential / incremental jobs until you have 100% of the data migrated and you can follow this up with its reports.
Post-migration: At this point you might have all of your users synced to the Cloud, with all security features enabled on Office 365 side as well as permissions, data migrated and rollback and new backup plan in place. In addition, be sure that all documentation handed out to end-user support, IT Staff or even from vendor is properly accessible as FAQs or within the proper SharePoint Sites or Intranets. Follow up with end uses on their post-migration experience while accessing new data and applications deployed. As per definition, except by the pilot phase the Migration could be targeted as a cutover phase where will require more planning, communication, training and tech support handling calls after the migration. It has been common to see migrations like waves when companies pick departments, users groups, offices or shared business departments when companies are merging or spiting and each scenario depends on variables such as budget, due dates and business requirements with more complexes processes and a well tested and exposure to any new technology that’s gonna be pushed to each company.
Backup (after migration): you can use Office 365 (OneDrive for Business and SharePoint Online) built-in backup and recovery options or you can use a third-party cloud-based backup solution for Office 365 (Exchange Online, OneDrive and SharePoint Online) which stores your data safe out of Microsoft structure. Your company security policies and compliance might not be satisfied with this model.

The basic scenario dealt with small, medium or large companies is pretty much the same regardless of the size of the company or how many users are going to be migrated. However, in the majority of the projects Personal Folders (home folder) are migrated to OneDrive for Business and Departmental Folders are in general migrated to Shared Document Libraries in SharePoint Online. In addition, you can backup your Documents, Pictures and Desktop folders with OndeDrive. Bare in mind that some type of data (legacy data, backup, staging files, etc.) can be migrated to Azure based on preliminary analysis and cost evaluation.

Tools offered by Microsoft to migrate data to OneDrive for Business and SharePoint Online are the following:

SharePoint Migration Tool: used for assessment, data summary and report and migration. SharePoint Migration Tool (SPMT) for SharePoint Servers 2010, 2013 and File Shares and that allows you to create and manage your migration tasks from a single computer or VM. Learn more
For large file share migrations spanning multiple computers or VMs use Migration manager. Therefore, SPMT is best for:
- Moving content from SharePoint Server 2010 or SharePoint Server 2013
- File share migration from a single computer or VM
- Migrating content to SharePoint Online, OneDrive and Teams
Migration Manager: The Migration Manager (Preview) helps you bring your on-premises file share content to the cloud whether you are moving a small set of files or working on an enterprise scale migration.
To get started, download and install the setup file for each agent. The agent must be a Windows computer or virtual machine.

On a practical scenario Global Administrator will give to the service account (migration account) required permission to OneDrive structure to have User’s personal folders migrated as a batch (where users are no longer responsible for their data migration). Similarly, to have data migrated over to SharePoint Online into Shared Document Libraries you need to check on-premises folder structure, permissions and supported file types.

References
https://support.office.com/en-us/article/types-of-files-that-cannot-be-added-to-a-list-or-library-30be234d-e551-4c2a-8de8-f8546ffbf5b3#ID0EAABAAA=Online *
https://support.office.com/en-us/article/invalid-file-names-and-file-types-in-onedrive-onedrive-for-business-and-sharepoint-64883a5d-228e-48f5-b3d2-eb39e07630fa?ui=en-US&rs=en-US&ad=US *