[DMS] Full Lob tasks lost connection

Please try the following:

• Set Timeout Strings: Ensure that all timeout settings referenced in the documentation are properly configured to accommodate the migration of large tables with LOBs. Pay particular attention to connection and execution timeouts.
• Ignore Foreign Keys: Consider disabling foreign key constraints during the migration process to prevent potential issues related to referential integrity.
• Optimize DMS Instance: Verify that the DMS instance (e.g., dms.r5.xlarge) has adequate resources to handle the migration workload. Consider scaling up the instance if necessary to improve performance.
• Address Connection Issues: Investigate and address any MySQL connection issues, such as "Connection Lost" errors or "Lost connection to MySQL server during query" messages. This may involve optimizing network settings, adjusting connection parameters, or troubleshooting connectivity issues.
• Check Replication Task Configuration: Review the replication task configuration, including parameters such as MaxFileSize and ParallelLoadThreads, to ensure they are appropriately set for the migration workload. Adjust these parameters as needed to optimize performance.
• Troubleshoot Failed Tasks: Analyze error messages related to failed replication tasks, such as "Failed to connect to database" or "Connection error [1022506]." Look for patterns or common issues that may indicate the root cause of the problem.
• Consider Full Load Only: If encountering persistent issues with CDC (Change Data Capture), consider using full load migration instead of CDC for the primary RDS instance. For read-only replica instances, full load migration may be sufficient.
• Monitor Resource Usage: Continuously monitor resource usage on both the source and target databases during the migration process. Look for any signs of resource contention or bottlenecks that may impact performance.
• Review Datbase Size and Structure: Validate the size and structure of the database, including the size of the table being migrated (e.g., 8GB with 15,995,900 rows). Ensure that the database schema is compatible with DMS migration.