Data Set Migration Without Client Shutdown
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional data migration processes are hindered by the need to shut down clients or wait for them to terminate access, leading to operational interruptions and prolonged migration times, especially when data sets are accessed and modified continuously.
Innovation Solution
A method that identifies applications accessing open data sets, updates their control information to reflect the new storage location, and establishes I/O intercepts to redirect requests, allowing migration without terminating applications or closing data sets, thus enabling seamless data set migration during ongoing operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional migration processes are used to move data sets from one storage device to another, then data sets can be migrated between storage locations, but client access must be terminated or the migration process cannot complete
Solution Approach 1:
The migration process is divided into distinct phases: mirror phase where data is copied to new storage device, and re-direction phase where clients are gradually redirected. This segmentation allows the migration to proceed without requiring complete client shutdown, as each phase can be executed independently while maintaining system availability.
Solution Approach 2:
A re-direction mechanism acts as an intermediary between clients and storage devices. During migration, this intermediary redirects client access requests from the old storage device to the new storage device, allowing seamless transition without clients needing to be aware of or terminate their connections.
2Productivity
If data sets remain open for continuous client access during migration, then business operations continue without interruption, but the migration process becomes never-ending due to constant changes in the data set
Solution Approach 1:
The mirror phase is executed preliminarily before the re-direction phase, creating a complete copy of the data set on the new storage device while clients continue to access the original data set. This preliminary action allows the migration to be completed in the background without affecting client operations, and the re-direction can occur atomically once the mirror is complete.
Solution Approach 2:
The system maintains continuous client access to data sets throughout the migration process by keeping the original data set open and accessible during the mirror phase, then seamlessly transitioning to the new storage device. This continuity ensures business operations proceed without interruption while the migration completes in the background.
3Reliability
If clients are shut down to complete migration, then the migration process can finish without ongoing changes, but business operations are interrupted causing revenue loss
Solution Approach 1:
The migration system dynamically adapts to ongoing client access patterns by continuously monitoring data set changes during the mirror phase and adjusting the migration timeline accordingly. The re-direction phase is triggered dynamically when the mirror completes, regardless of client access patterns, allowing migration completion without requiring planned shutdowns.
Data Source
AI summary
A method for performing data set migration includes receiving a request to migrate data sets, finding the systems with the data sets open, establishing at least one I/O intercept, copying the data set, mirroring changes to the data set, updating control information in the systems with the data sets open, and terminating the at least one I/O intercept.