Archiving and retrieval of experimental data using SAN based centralized storage system for SST-1

Abstract

SAN (Storage Area Network, a high-speed, block level storage device) based centralized data storage system of SST-1 (Steady State superconducting Tokamak) has envisaged to address the need of availability of SST-1 operation & experimental data centrally for archival as well as retrieval [2]. Considering the initial data volume requirement, ∼10TB (Terabytes) capacity of SAN based data storage system has configured/installed with optical fiber backbone with compatibility considerations of existing Ethernet network of SST-1.The SAN based data storage system has been designed/configured with 3-tiered architecture and GFS (Global File System) cluster file system with multipath support. Tier-1 is of ∼3TB (frequent access and low data storage capacity) comprises of Fiber channel (FC) based hard disks for optimum throughput. Tier-2 is of ∼6TB (less frequent access and high data storage capacity) comprises of SATA based hard disks. Tier-3 will be planned later to store offline historical data. In the SAN configuration two tightly coupled storage servers (with cluster configuration) are working together to achieve increase performance, reliability, distribute workload and provides access to the files from any server regardless of the physical location of the file. Different RAID (Redundant Array of Independent Disks) groups are created with both, FC and SATA hard disks to increase reliability, security and performance of the storage system.The adopted SAN based data storage for SST-1 is a modular, robust, and allows future expandability. The storage modules can be added as and when required without changing the existing storage architecture. The data read/write time of the configured system is adequate enough to cater the present throughput requirements of individual subsystems. Sufficient redundancy in terms of hardware has been incorporated to assure the uninterrupted experimental data availability 24×7 within intranet. The installed storage system can be expanded up to ∼100TB of capacity with the existing controller pair presents in the SAN configuration.