Troubleshooting the server/data center migration to cloud issue of HTML for Confluence app stuck at 0%

Issue Description

Migrating Confluence from a server or Data Center to the Cloud can sometimes be complex, particularly when the migration stalls at 0%. Here’s a detailed guide to troubleshooting and resolving this issue using the Confluence Cloud Migration Assistant (CCMA).

Solution

Steps to troubleshoot migration issues

Pre-migration Checks

1. Pre-migration Steps: Ensure all pre-migration steps are completed as specified in the documentation. This includes preparing the environment and validating the prerequisites.

2. Handling large data loads: If the pre-migration stalls, especially with large data loads, consider directly updating the database as a workaround. Execute the recommended queries and reindex Confluence to resolve stalling issues potentially.

3. Macro Update status: If the macro update status does not reflect the changes, disable and re-enable the HTML for confluence, then verify the status again.

Migration Preparation

1. Update CCMA: Ensure the Confluence Cloud Migration Assistant is up-to-date before initiating the migration process.

2. Install HTML for Confluence App: Verify that the HTML for Confluence app is installed on the cloud instance.

3. Clear Warnings and Errors: Address all warnings and errors that appear during the preparation phase to ensure a smooth migration.

Migration Process

1. Stalled Migration at 0%: If the migration appears stuck at 0% on the Migration Assistance page, perform the following checks:

   • Data verification: Compare the data between the server and cloud instances using HTML data to confirm if the migration is progressing despite the UI showing 0%.

   • Profile configuration: Ensure that profiles are migrated and configured correctly on the global configuration page.

2. Macro Usage verification: Check the macro usage on both the server and cloud sides to confirm data migration, even if the UI shows 0%. To learn about macro usage, log in as Confluence Admin → Settings → Administration → Macro usage. Another option is to use Confluence Advanced Search to find the pages where a particular macro is used.

Handling Specific Issues

1. No Profile configured: If profiles are not configured in the Data Center, perform a migration specifically for the HTML for Confluence app data. Reinstall the app on the Cloud and migrate only the app without needing to migrate the spaces again.

2. Persistent issues: If issues persist despite following these steps, contact the support team. Provide them with debug logs and a screenshot of the migration page for further assistance.