RAID Cache Backup Using Disk Security Areas During Recovery

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing RAID systems face data loss in cache during restoration due to faulty disks or controllers, leading to operating system failures and user data loss.

Innovation Solution

Implementing a security area in disks to back up cache data, allowing data to be restored from the security area after system restoration, and ensuring data consistency before flushing to avoid loss.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the cache data is cleared before disk restoration to ensure data compatibility, then the data consistency between new disks and cache is improved, but the cache data is lost

Engineering Contradiction:
Improvedata compatibilityVSAvoidcache data loss
Core Design Contradiction:
Manufacturing precisionVSLoss of information

Solution Approach 1:

The patent applies preliminary action by detecting the offline status of the RAID system and proactively copying cache data to disks before restoration operations begin. This ensures cache data is preserved and can be restored later, avoiding data loss while maintaining compatibility during the restoration process

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements copying by creating a backup copy of cache data on disk storage. The cache data is copied to disks when the RAID system is detected as offline, and this copied data is later restored to the cache after restoration, preserving the original cache data while enabling safe restoration operations

Inventive Principle:
Principle #26Copying

2Productivity

If the RAID controller is directly replaced to restore the offline RAID system, then the restoration speed is improved, but the original data in the cache is lost

Engineering Contradiction:
Improverestoration speedVSAvoidcache data loss
Core Design Contradiction:
ProductivityVSLoss of information

Solution Approach 1:

The patent applies preliminary action by detecting the offline status and copying cache data to disks before the RAID controller is replaced. This preliminary data preservation enables the new controller to restore cache data after installation, maintaining both fast restoration and data preservation

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements copying by creating a backup of cache data on disk storage before controller replacement. The copied cache data is then restored by the new controller after it takes over, ensuring no data loss occurs during the controller replacement process

Inventive Principle:
Principle #26Copying

3Loss of information

If the data in the cache is not cleared before disk restoration, then the cache data is preserved, but the data in new disks may be incompatible with data in the cache

Engineering Contradiction:
Improvecache data preservationVSAvoiddata compatibility
Core Design Contradiction:
Loss of informationVSManufacturing precision

Solution Approach 1:

The patent implements copying by creating a backup copy of cache data on disk storage. This copied data serves as a reference during restoration, allowing the system to verify and maintain data compatibility while preserving the original cache data for later restoration

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The patent applies feedback by detecting the offline status of the RAID system and using this information to trigger cache data copying operations. The system continuously monitors RAID status and adjusts cache management operations based on the detected state, ensuring data compatibility is maintained while preserving cache data

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP4027243B1Data recovery method and related device
Publication Date: 2025.12.03 HUAWEI TECH CO LTD
  • EP4027243B1 patent drawingFigure 1
  • EP4027243B1 patent drawingFigure 2~3
  • EP4027243B1 patent drawingFigure 4

AI summary

A data restoration method and a related device are provided. To avoid a data loss in a cache in a process of restoring an offline RAID system, a security area is configured in a disk, where the security area is used to back up data in the cache of a RAID controller after the RAID system is offline. Therefore, when a first instruction used to indicate that the RAID system is offline is obtained, the data in the cache may be backed up to the security area. In this way, after the RAID system is restored, the RAID system can obtain backup data of the data in the cache from the security area, to avoid problems such as an operating system startup failure or a user data loss caused by the data loss in the cache.