Data Consistency in Office 365 Migrations

Understanding and Handling Investigate Status in Data Consistency Scoring

office 365 migration server data storage

Key Highlights

Data Consistency Score (DCS): A quantitative measure to assess migration integrity and detect inconsistencies.
Investigate Grade: Indicates minor yet critical data issues that require manual review or approval to proceed with migration.
Best Practices & Automation: Detailed steps for monitoring, troubleshooting, and automating the approval process using tools such as PowerShell.

Overview of Data Consistency in Office 365 Migrations

In the process of migrating data to Office 365, ensuring that the integrity and consistency of data remain intact is critical. Microsoft introduced the Data Consistency Score (DCS) as a systematic way to evaluate the quality of data migration. DCS provides a structured grade that reflects how well data has been transferred from a source environment—often an on-premises Exchange Server, PST files, or other platforms—to Office 365. This scoring system replaces older methods that relied on setting limits for "bad items" and provides a detailed analysis of potential data inconsistencies encountered during the migration process.

The migration may result in a range of outcomes from an ideal "Perfect" score, where no data inconsistency is detected, to a "Poor" rating that signals significant issues requiring immediate intervention. Administrators can monitor the migration along both the user and batch levels by accessing these scores via the Microsoft 365 Admin Center. One of the critical categorizations within this system is the "Investigate" grade, which indicates the presence of inconsistencies or minor data loss that may not completely halt the migration but necessitate further review and manual intervention.

Understanding Data Consistency Score (DCS)

What is DCS?

The Data Consistency Score is designed to assess the fidelity of migrated data in Office 365 migrations. It grades migrations using a set of predefined categories based on detected inconsistencies:

Perfect: Indicates zero inconsistency with an ideal match between source and target data.
Good: Minor inconsistencies exist, but they are unlikely to affect overall functionality.
Investigate: Reflects the existence of small amounts of data loss or inconsistencies that, while not halting the migration, require proactive review and approval of skipped items.
Poor: Significant inconsistencies are found, seriously affecting data integrity and requiring external support intervention before migration can proceed.

The "Investigate" status often appears when certain items have been skipped during the migration due to issues like corrupt data, orphaned permissions, or items exceeding the Office 365 size limits (e.g., items over 150MB in hybrid migrations). These challenges prompt the need for manual oversight to ensure that no critical data is lost and that the migration remains on track.

By shifting from a fixed "bad item" limit to the more dynamic DCS framework, organizations now have a more nuanced tool to evaluate and manage data inconsistencies, which allows for targeted interventions when issues are identified.

Deeper Dive into the “Investigate” Grade

Definition and Implications

The "Investigate" grade in the DCS framework signals that while the overall data migration might be successful, there exist specific items or inconsistencies that are categorized as problematic. These issues are generally minor, involving small-scale data loss or skipped items due to:

Corrupt Data or Properties: Some data items become corrupted, causing difficulties during the transfer process.
Orphaned Permissions: In some cases, permissions attached to items may not correctly map over to Office 365, leaving data with incomplete or missing security configurations.
Oversized Items: Particularly in hybrid environments, items that exceed the size limit (commonly 150MB) may be flagged and omitted from the migration.
Missing Data: Occasionally, specific attributes or metadata in the source do not correctly propagate to the target environment, resulting in consistency issues.

When the DCS identifies an "Investigate" status, it essentially sends a signal to the IT administrator to review these discrepancies carefully. The inconsistencies, although minor, could accumulate and potentially affect user experience or operational integrity if not resolved. It is important for administrators to determine whether these issues involve critical data.

Investigating and Approving Skipped Items

In many cases, the solution for handling "Investigate" graded migrations is to manually approve the skipped items. This ensures that the migration is not halted while recognizing minor inconsistencies that require further attention. It also helps preserve workflow continuity:

Manual Review Process: Administrators can review the detailed migration reports in the Microsoft 365 Admin Center to inspect the items flagged for investigation. This process may involve checking file properties, verifying metadata, or comparing source data with what has been successfully migrated.
Automated Approval via PowerShell: To streamline this task, especially for large-scale migrations, administrators can utilize PowerShell scripts. A common script filters migration users with an "Investigate" score and automatically approves the flagged skipped items. For instance, the PowerShell snippet below can be used:
```
# Get migration users with an Investigate status and approve skipped items
Get-MigrationUser | Where-Object { $_.dataconsistencyscore -eq 'Investigate' -and $_.status -eq 'NeedsApproval' } | Set-MigrationUser -ApproveSkippedItems
      
```

Such automation facilitates the process, reducing manual workload and ensuring that the migration continues smoothly without neglecting the minor inconsistencies. However, automation should be applied judiciously in cases where the minor discrepancies do not involve critical data.

Best Practices for Handling Data Consistency Issues

Pre-Migration Preparation

Before beginning any migration, it is essential to lay a strong foundation to minimize potential data consistency issues:

Comprehensive Data Backup: Always ensure that you have full backups of the source data. In the event of any data inconsistency, this backup allows you to restore or verify the data.
Data Assessment: Conduct preliminary analyses to understand the nature of your data. Identify items that might pose issues based on size, complexity, or data fields that are unusual or prone to errors.
Pre-Migration Testing: Run test migrations on sample datasets to observe how the DCS reacts. This early feedback can highlight potential problem areas before the full migration is undertaken.
Familiarize with Office 365 Limitations: Understanding key limits (such as item size limits for hybrid migrations) is crucial. Adjust your data or migration plans accordingly.

Monitoring During Migration

Active monitoring during the migration phase is essential to quickly react to any raised inconsistencies:

Regular Review of DCS Reports: Constantly check the migration dashboard within the Microsoft 365 Admin Center. The DCS reports are available at both the individual mailbox and batch migration levels. This allows you to promptly address any emerging issues.
Error Logging and Alerts: Configure error logging and alerts so that you are immediately informed when a migration falls into the "Investigate" or "Poor" categories. This real-time vigilance helps preempt larger data integrity issues.
Collaborate with IT Teams: Integrate communication channels with your IT support team to ensure that any flagged issues are quickly assessed and addressed. This may include rearranging migration priorities based on the severity of flagged items.

Post-Migration Validation

After the migration is completed, validate that all data has been successfully and accurately transferred:

Detailed Data Reconciliation: Perform reconciliation between the source environment and Office 365. This ensures that no critical data has been omitted or altered during migration.
User Acceptance Testing: Engage a sample of end users to verify they can access and interact with their data as expected. This real-world testing can sometimes reveal issues that were not caught in technical reports.
Post-Migration Reporting: Generate and review detailed reports detailing the final DCS grades. This documentation is essential for audit purposes and for planning any necessary adjustments or re-migration efforts.

Data Consistency Scoring Grading Table

Grade Descriptions and Implications

The table below summarizes the grading system within the Data Consistency Score and what each grade represents:

Grade	Description	Implication
Perfect	No inconsistencies detected in the migrated data.	Migration is complete with exact data fidelity.
Good	Minor inconsistencies, such as small metadata discrepancies.	Data is largely intact with negligible impact on functionality.
Investigate	Some data loss or skipped items due to corrupt data, orphaned permissions, or oversized items.	Requires manual review and possible approval for skipped items; not critical but must be remedied.
Poor	Significant inconsistencies affecting important data.	Immediate intervention and support assistance required before migration can proceed.

Using PowerShell to Automate and Manage "Investigate" Items

PowerShell for Streamlined Management

Automating the handling of skipped items that fall into the "Investigate" category can save valuable time and reduce manual errors. PowerShell is a powerful administrative tool that can be utilized to approve these items en masse. The approach involves filtering migration users with an "Investigate" status and applying a command to approve the items that require manual intervention.

For instance, the following PowerShell script exemplifies a typical automation routine:


# Retrieve all migration users with an "Investigate" Data Consistency Score
# and automatically approve their skipped items to proceed with migration.
Get-MigrationUser | Where-Object { $_.dataconsistencyscore -eq 'Investigate' -and $_.status -eq 'NeedsApproval' } | Set-MigrationUser -ApproveSkippedItems

This script serves to approve the same items that were flagged under the "Investigate" category, thereby ensuring that the migration does not stall due to minor issues. It is important to note that while automating this process is efficient, administrators should balance automation with periodic manual checks to confirm that no critical data is inadvertently overlooked.

Challenges and Considerations

Identifying and Handling Critical Data

Certain challenges remain even with the robust framework provided by Data Consistency Score. One of the recurring issues is ensuring that the items flagged as "Investigate" do not include essential data that might impact business operations if not properly resolved.

To mitigate these challenges, organizations should implement robust data validation procedures. This involves a combination of automated assessments and human oversight. Critical steps include:

Data Prioritization: Not all data is equal. Identify key datasets that are mission-critical and ensure extra scrutiny during the migration process.
Manual Spot Checks: Even with automation, performing random manual checks on migrated data can help validate the automated approvals and catch any anomalies that scripting might have missed.
Pre-migration Data Cleansing: Address corrupt or problematic data prior to migration to reduce the likelihood of facing significant issues during the move. Data cleansing can be an important step in normalizing the datasets to a state that is optimal for migration.

Balancing Automation with Oversight

While automation tools significantly reduce administrative overhead during migrations, they must be balanced with sufficient oversight. In situations where multiple users or large datasets are involved, it is crucial to set up monitoring mechanisms that can identify discrepancies rapidly. Version control, logging, and alert systems are part of a comprehensive strategy to ensure that automation does not lead to overlooked anomalies.

In summary, Data Consistency Score and its "Investigate" grade enable administrators to maintain high data fidelity without overwhelming manual processes. A combination of effective pre-migration planning, continuous monitoring during the migration, and post-migration validation assures that data integrity remains uncompromised as organizations transition to Office 365.

Conclusion

Migrating to Office 365 is a complex process that requires careful planning and meticulous execution to ensure that data remains consistent and reliable throughout the transition. The Data Consistency Score offers a systematic approach to gauge the fidelity of the migration, categorizing the process into grades that reflect the overall health of the data transfer.

Specifically, the "Investigate" grade highlights scenarios where minor data inconsistencies or skipped items occur. These issues, while not immediately critical, must be reviewed and approved—either manually or via automated PowerShell scripts—to prevent potential disruptions in the post-migration environment. By establishing best practices such as comprehensive pre-migration data backups, diligent real-time monitoring, and stringent post-migration validations, organizations can minimize risks and maintain operational continuity.

Employing a balanced mix of automation and manual oversight ensures that even as data inconsistencies are addressed swiftly, no critical data is left unverified. This robust framework allows for a smooth migration path to Office 365, providing IT administrators with the transparency needed to identify, analyze, and resolve issues promptly. Overall, the combined emphasis on data integrity through proactive monitoring and responsive support makes the DCS an indispensable tool in modern data migration strategies.

References

Migrations with Data Consistency Score (DCS) – more than you ever wanted to know - Microsoft Tech Community
Improving Migrations Using Data Consistency Scoring - Microsoft Tech Community
Data Consistency Scoring for Exchange Online Mailbox Migrations - Practical365
Track and Prevent Migration Data Loss in Exchange Online - Microsoft Learn
Data Consistency Scoring in Migrations To Exchange Online - Mad Mike