Exploring Networked Storage :Exploring Networked Storage DS Giri dharmendra.giri@gmail.com http://SliceData.BlogSpot.com


Categorizing Storage - DAS – SAN - NAS :Categorizing Storage - DAS – SAN - NAS Directly Attached Storage – DAS – Storage that is connected point-to-point with a server – Originally on the SCSI Bus but also serial attached devices Storage Area Network – A network that enables block level (raw) storage to be accessed from multiple servers – Mainly based on Fibre Channel but iSCSI has about 5% revenue Networked Attached Storage – Shared files (cooked storage) that are accessed over the LAN – Originally a server that delivers shared files – ~25% of the revenue of External Storage Internal External Over $13B spent on external storage in 2006 to surpass internal for the first time.


Fibre Channel Replaces the SCSI Bus :Fibre Channel Replaces the SCSI Bus SCSI Bus lead to captive storage with only 1 server (initiator) per bus Fibre Channel liberated storage so that multiple servers could access it at the same time Fibre Channel extended the distance and increased the speed of Storage I/O to Gigabit per second speeds (Gbps) Internet SCSI (iSCSI) has mapped the SCSI protocol on top of Transmission Control Protocol (TCP/IP) Fibre Channel Over Ethernet (FCoE) is being designed to encapsulate FC frames and transfer them over Ethernet networks


Volume to Mid-Range Storage :Volume to Mid-Range Storage Volume Storage Arrays contain 10s of disks for a few Terabytes of capacity • 2 to 8 2GFC Links/ storage Array – 2-10+ Gbps of throughput Midrange Storage Arrays contains 100s of disks for 10s of Terabytes of capacity • 4 to 24 2/4GFC Links/ storage Array – 10s of Gbps of throughput GFC = Gigabit/second Fibre Channel


High End Storage :High End Storage Over 1,000 disk drives for 100s of TBs in a storage subsystem • 64+ lanes of 2-4GFC – exceeding 100 Gbps of throughput


Network Attached Storage (NAS) :Network Attached Storage (NAS) NAS is storage on the LAN that share files (file level storage) while SANs share Block level storage behind servers • NAS products host shared drives (think m: or v: drives) • End users quickly began storing and sharing large amounts of computer files • Unstructured file (end user) data is the fastest growing data type – think powerpoint, excel, photos and MP3s Large NAS heads or filers have Ethernet front ports and Fibre Channel back ports


NAS Products :NAS Products NAS file-based products follow the same progression of SAN’s block-based storage products Volume systems may have a few TeraBytes of Directly Attached Storage with a few Gigabit Ethernet front end ports High end systems hold hundreds or TBs of SAN attached storage and tens of FC and GE ports and even 10GE ports


High Level Overview with NAS :High Level Overview with NAS


Conclusion :Conclusion SANs are the basis for storage and server consolidation that drives 10s to 100s of Gbps of throughput NAS is an application that consumes a large amount of storage and serves a large amount of files in the few to tens of Gbps range Virtualization of Servers, switches and storage increases utilization of physical assets and bandwidth in the SAN space Corporate networks are converging with Fibre Channel over Ethernet (FCoE) being defined as the latest “Unified Wire” protocol in T11 and IEEE


Thank You :Thank You