Seeking an alternative to tape-based custodial storage

Abstract

In November 2018, the KISTI Tier-1 centre started a project to design, develop and deploy a disk-based custodial storage with error rate and reliability compatible with a tape-based storage. This project has been conducted in collaboration with KISTI and CERN; especially the initial design was laid out from the intensive discussion with CERN IT and ALICE. The system design of the disk-based custodial storage consisted of high density JBOD enclosures and erasure coding data protection, implemented in EOS, the open-source storage management developed at CERN. In order to balance the system reliability, data security and I/O performance, we investigated the possible SAS connections of JBOD enclosures to the front-end node managed by EOS and the technology constraints of interconnections in terms of throughput to accommodate large number of disks foreseen in the storage. This project will be completed and enter production before the start of LHC Run3 in 2021. In this paper we present the detailed description on the initial system design, the brief results of test equipment for the procurement, the deployment of the system, and the further plans for the project.