Verify migrations

Data Migrator migrates data from a source to a target filesystem, including rapidly changing transactional data. Occasionally, a migration can run into problems, such as:

• Service failures or interruptions.
• Software errors or individual file migration failures.

Use migration verification to scan the source and target, and check data on the source is also on the target. The verification compares the source and target for any discrepancies to allow you to check your migration status.

Discrepancies

Include	Don't include
Data that exists on one side and not on the other.	Changes made after a specified time (see Verification Cutoff Point below).
File size mismatches.	Exclusions.

info

Adding exclusions to an active migration may cause discrepancies.

Files migrated to the target before adding the exclusion are listed as discrepancies because they exist on both the source and target.

• An excluded file that exists on both the source and target (FOUND_ON_BOTH) is a discrepancy.
• An excluded file that exists on the source (FOUND_ON_SOURCE) but not the target isn't a discrepancy.

note

Full verification reports list all excluded files.

Limitations and considerations

• Only one verification can be active at a time for each data migration.
• You can run verifications on different migrations at the same time.
• LiveData Migrator for Azure can run a maximum of 10 verifications at the same time and queues any additional verifications until older ones are completed.
• If you find a discrepancy in the full report that was a modification to the source or target and was made after the verification start time, it isn't a true discrepancy.
• LiveData Migrator for Azure doesn't check any files and directories that are excluded from the migration for discrepancies. The summary report shows the number of files and directories excluded on the source.
• Verifications with path mappings are supported, where the root of the migration is mapped. Path mappings within the migration aren't included.

Prerequisites

Migrations must have one of the following statuses to perform verification scans:

• LIVE (real-time event stream notifications for changes to the source that are replicated to the target)
• COMPLETED (one-time migration without event stream notifications)
• PAUSED (a user has stopped the migration manually)

note

You can’t verify a migration that is in RUNNING state. Wait for the migration to finish or stop it and run the verification scan.

Verify migration with Azure Portal

To add a new migration verification perform the following steps in the Azure Portal:

1. In the Azure Portal, navigate to the LiveData Migrator resource page.
2. From the LiveData Migrator menu on the left, select Migrations.
3. Select the migration you want to verify.
4. From the menu on the left, select Verification.
5. Select Add.
6. Complete the Migration Verification Basics configuration:
   • Verification Name: Enter a name for this verification.
   • Path to Verify: Enter the path or paths from your source or target filesystem you want to verify using the format /path/to.
7. Select Verification Options.
8. Complete the Verification Options configuration:
   • Verification Depth: Enter a number to specify how deep in the directory you want to run the verification check. The number must be equal to or less than the total number of levels in the directory structure of your migration.
     Zero means there's no limit to the verification depth.
   • Verification Cutoff Point: Select a date and time as a verification cutoff point. The verification checks files modified on the source filesystem before the date and time you specify and excludes any changes after that cutoff point.
9. Select Review + Create to review your current configuration.
10. Select Review + Create again to create your migration verification.

Verify migration with Azure CLI

To add a new migration verification use the az livedata migrator verification command with the Azure CLI:

az livedata migrator verification create -g resourceGroupName --migrator-name migratorName --migration-name migration1 --verification-name verification --verification-depth 0 --original-paths "/repl1" --ignore-after-timestamp 2023-01-09T10:05:31.000Z

View a verification summary report

The verification summary report is updated with information from the source and target found during the verification scan.

The report will contain:

• The number of files and directories found on the source and the target
• Total amount of data on the source and the target
• Total number of inconsistencies found, including file size mismatches, missing or extra files and directories on the target

To view the report use the following steps:

1. In the Azure Portal, navigate to the LiveData Migrator resource page.
2. From the LiveData Migrator menu on the left, select Migrations.
3. Select the migration you want to verify.
4. From the menu on the left, select Verification.
5. Select the verification you want to check.
6. Select Overview from the menu on the left to view the verification summary.

Download a full verification report

A full text version of the verification report will be saved to your LiveData Migrator for Azure installation directory. /opt/wandisco/livedata-migrator/<instance>/db/verifications/ You can also find the download location from the "reportLocation" field of the verification resource.