In 2012 CSCS will move from its actual location in Manno to the nearby city of Lugano. The geographical distance between the current and the future location is about 3 km, the measured distance of dark fiber is 10km.
CSCS evaluated the Obsidian Longbow InfiniBand Range Extender with the overall goal to ensure continuous availability of GPFS through the complete CSCS relocation period by running one single GPFS file system over both sites.
InfiniBand Fabrics are designed to serve the needs of HPC computing and HPC storage. The increase in distribution of computational workloads to sites in different locations and also the ongoing trend for infrastructure consolidation at large research sites creates the necessity to investigate in alternatives to Fiber Channel or iSCSI over Ethernet in order to realize high performance network connections over wide distances.
Three application areas should benefit from this solution: Storage Area Networks by enabling inter-building SANs, Cluster Aggregation and remote visualization.
Various solutions exist in the market for High-Performance Connectivity with InfiniBand over the WAN. As an example, InfiniBand Range Extensions are supplied by Obsidian, Bay Microsystem and Net.com.
Net.com offers NX5010, where performance is limited to the use of TCP/IP protocols. Bay Microsystems provides the IBEx G40/M40 InfiniBand Extension Switch which utilizes proprietary packet and transport-processing technology and allows the IBEx G40 device to seamlessly transport native InfiniBand over most wide-area network technologies.
Obsidian proposes an interesting technology that uses solely optical fiber and has been evaluated by Xiangyong Ouyang et al. Since proprietary optical encoding is deployed, the devices must be deployed in pairs, connected by direct light paths. When installed, the Longbows appear and behave like native InfiniBand switches.
The motivation for the investigation of this technique at CSCS is based on the center´s requirements during its relocation in early 2012. This technology is a potential solution to keep our central parallel file system (GPFS) up and running throughout the relocation period from March 2012 to June 2012, when CSCS will move from its current location in Manno to Lugano.
Results of the Study
Based on the results of the evaluation study, CSCS decided to deploy the Obsidian InfiniBand Range Extender C103 Series for the migration of User data from the current location in Manno to the new center in Lugano-Cornaredo.
According to CSCS the performance will be sufficient for migrating the complete GPFS File system (about 1.5 PB) between both sides within a few weeks.
The key characteristics of resilience have been analyzed and convinced that the Obsidian technology is a very cost-efficient and reliable solution to complete the relocation until June 2012.