Central Controller Logical Unit Reset in Distributed Storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In distributed storage systems, implementing a logical unit reset command across multiple functional entities is challenging due to the need for coordinated action across various interfaces, with existing solutions lacking efficient mechanisms for handling failures and ensuring high availability.
Innovation Solution
A method and system that involve a central controller initiating and managing a logical unit reset across multiple interfaces, including writing session-data, communicating commands, and handling failures by utilizing a backup controller to ensure continued operation and high availability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a logical unit reset command is implemented across multiple interfaces in a distributed storage system, then the reliability of the reset operation is improved, but the complexity of coordinating action across various interfaces increases
Solution Approach 1:
A session coordinator entity is introduced as an intermediary to manage the reset operation across multiple interfaces. The coordinator receives the reset command, initiates sessions at participating interfaces, collects session data, and coordinates the overall reset process, thereby reducing the coordination complexity while ensuring reliable reset operation across the distributed system
Solution Approach 2:
The reset operation is segmented into multiple independent session operations at different interfaces. Each interface executes its own session independently, and the session data from each interface is collected and combined. This segmentation allows parallel execution while maintaining coordination through the session data aggregation mechanism
2Speed
If session data is maintained in memory without persistent storage, then the speed of failure recovery is improved, but the risk of data loss increases
Solution Approach 1:
Session data is maintained in memory for fast access and recovery, and simultaneously copied to persistent storage as a backup. Upon failure, the system can quickly restore from the in-memory copy while the persistent copy ensures data safety, thus achieving both fast recovery and data protection
Data Source
AI summary
A method of implementing a logical unit reset across a plurality of interfaces in a distributed storage system, comprising: initiating a session for implementing the logical unit reset across the plurality of interfaces in response to receiving at a central controller a logical unit reset command from an originator interface, and writing session-data including an indication that the originator interface implemented the respective logical unit reset locally; communicating a logical unit reset command from the central controller to each interface other than the originator interface; updating the session data in response to receiving an indication from an interface that the logical unit was successfully reset locally and when each one of the plurality of interfaces implemented the logical unit reset locally, communicating a success response to each one of the plurality of interfaces.