Archive Task Team (ATT)
Disk Storage
Stuart Doescher, USGS(Ken Gacke)WGISS-18
September 2004Beijing, China
Storage TechnologiesStorage Technologies
• Online Storage– Direct Attach Storage (DAS)
• Storage directly attached to server
– Network Attach Storage (NAS)• TCP/IP access to storage typically with CIFS and NFS access
– Storage Area Network (SAN)• Dedicated high speed network connecting storage devices• Storage devices disassociated from server
Storage TechnologiesStorage Technologies• Direct Attach Online Storage
– Disk is direct attached to single server– System Configuration
• SCSI or Fibre Channel– RAID Fibre Channel devices are typically SAN ready
• Just a Bunch of Disk (JBOD)• Redundant Array Independent Disk (RAID)
– High Performance on the local server– Manageability
• Simple Configuration• Resource reallocation requires physical move of
controllers and disk
Storage TechnologiesStorage Technologies
Direct Attached
Host A
File System
Host B
File System
Host C
File System
100Mb Network (FTP/NFS)
100MB FC
Storage TechnologiesStorage Technologies
• Direct Attach Online Storage– Advantages
• High performance on local server• Good for image processing and database applications
– Disadvantages• Data sharing limited to slower network performance • Difficult to reallocate resources to other servers
Storage TechnologiesStorage Technologies
• NAS Online Storage– Disk attached on server accessible over TCP/IP Network– System Configuration
• Fibre Channel RAID Configurations• Switched Network Environment
– Performance• Network Switches and/or dedicated network topologies
– Reliability• NAS Server performs a single function thereby reducing faults• RAID, Mirror, Snapshot capabilities
– Easy to Manage
Storage TechnologiesStorage Technologies
Network Attached1Gb Network (NFS/CIFS)
Host A Host B Host C
File System
File System
File System
Share Files
NASServer
Storage TechnologiesStorage Technologies• Network Attach Online Storage
– Advantages• Easy to share files among servers
– Network Storage support NFS and CIFS– Servers can use existing network infrastructure
• Good for small file sharing such as office automation• Availability of fault protection such as snapshot and
mirroring– Disadvantages
• Slower performance due to TCP/IP overhead• Increases network load• Backup/Restore to tape may be difficult and/or slow• Does not integrate with nearline storage
Storage TechnologiesStorage Technologies
• SAN Online Storage– Disk attached within Fabric Network– System Configuration
• Fibre Channel• RAID Configurations
– Scalable High Performance– High Reliability with redundant paths– Manageability
• Configuration becomes more complex• Logical reallocation of resources
Storage TechnologiesStorage Technologies
Host A
Host B
Host C
Redundancy SAN Configuration
100Mb Network
FibreSwitch
(DMF)
FibreSwitch
Storage TechnologiesStorage Technologies
• SAN Online Storage Architecture– Disk Farm
• Multiple servers share large disk farm• Server mounts unique file systems
– Clustered File Systems• Multiple servers share a single file system• Software Required – Vendor solutions include
– SGI CXFS – ADIC StorNext File System– Tivoli SANErgy
Storage TechnologiesStorage Technologies
Host A
Host B
Host C
Disk Farm SAN Configuration
100Mb Network
FibreSwitch
Logicalreallocationof disk
Storage TechnologiesStorage Technologies
• SAN Risks– Cost is higher than DAS/NAS– Technology Maturity
• Solutions are typically vendor specific• Application software dependencies
– Infrastructure Support• Complexity of Architecture• Management of SAN Resources• Sharing of storage resources across multiple
Programs/Projects
Storage TechnologiesStorage Technologies• SAN Benefits
– Administration flexibility• Logically move disk space among servers• Large capacity drives can be sliced into smaller file
systems• Scales better than direct attach• Integrate within nearline configuration
– Data Reliability• Storage disassociated from the server• Fault Tolerant with Redundant Paths
– Increase Resource Utilization• Reduce the number of FTP network transfers• Logically allocate space among servers
Storage TechnologiesStorage Technologies
Host A
Host B
Host C
SAN with Nearline Configuration
1Gb Network
FibreSwitch
CXFS
DMF/CXFS
ClusteredFile System
Tape Library
CR1 SAN/Nearline ArchitectureCR1 SAN/Nearline Architecture
DMF Server
Product Distribution
Tape Drives 8x9840 2x9940B
1Gb Fibre
2Gb Fibre
Disk Cache /dmf/edc 68GB/dmf/doqq 547GB/dmf/guo 50GB/dmf/pds 223GB/dmf/pdsc 1100GB
Ethernet
Future Seamless/Silo Future Seamless/Silo ArchitectureArchitecture
Ethernet
DMF
PDS
Tape Library 8x9840 3x9940B
FTP (lxs37)
Web/ExtractTP9300S3TB
TP9400
CIFSMount
Data Servers
Storage TechnologiesStorage Technologies• Multi Tiered Storage Vision
– Online• Supported Configurations
– DAS – Local processing such as image processing– NAS – Data sharing such as office automation– SAN – Production processing such as product
generation• Data accessed frequently
– Nearline• Integrated within SAN• Scalable for large datasets and less frequently accessed
data• Multiple Copies and/or Offsite Storage
Storage TechnologiesStorage Technologies
• SAN – Final Thoughts– SAN Technology Maturity
• SAN solution should be from a single vendor– Program/Project SAN solution benefits
+ Decrease storage requirements+ Increase performance+ Increase reliability+ Increase flexibility of resource allocations- Increase cost (hardware/software)- Increase configuration complexity
Storage Architecture DecisionsStorage Architecture Decisions
• Optimized by individual program and program manager, not the enterprise.
• Requirements Factors– Reliability – Data Preservation– Performance – Data Access– Cost – $/GB, Engineering Support, O&M– Scalability – Data Growth, Multi-mission, etc.– Compatibility with current Architecture
• Evaluated and recommended through engineering white papers and weighted decision matrices.
Bulk RAID Weighted MatrixBulk RAID Weighted MatrixSelecton Criteria RW #
Nexsan Ataboy2
CESATA
EMC SATA
STK B220
STK D240
Initial Cost 10 10 10 7 9 6Support Cost 10 10 9 5 8 6
Vendor Support 2 5 3 9 9 9EDC Experience 0 6 5 6 7 8
Performance 5 6 6 7 7 9Reliability 1 6 3 7 7 9
Manageability 5 7 4 7 9 9Scalability 1 5 5 7 7 8
SAN Ready 1 8 0 8 8 8Upgradeable 1 5 3 9 9 8
Weighted ScoreNexsan Ataboy2
CESATA
EMC SATA
STK B220
STK D240
Initial Cost 100 100 70 90 60Support Cost 100 90 50 80 60
Vendor Support 10 6 18 18 18EDC Experience 0 0 0 0 0
Performance 30 30 35 35 45Reliability 6 3 7 7 9
Manageability 35 20 35 45 45Scalability 5 5 7 7 8
SAN Ready 8 0 8 8 8Upgradeable 5 3 9 9 8
Total Weighted Score 299 257 239 299 261
High Performance RAID Weighted High Performance RAID Weighted Matrix Matrix
Selecton Criteria RW #EMC
CX300EMC
CX500STK D240
STK D220
Ciprico FibreSt
Adaptec SANbloc
NexSan Ataboy
Initial Cost 9 8 5 6 7 4 10 10Support Cost 9 4 4 6 6 5 10 10
Vendor Support 8 9 9 9 9 8 7 5EDC Experience 6 7 7 8 8 7 5 6
Performance 8 8 8 9 8 6 7 6Reliability 9 9 9 9 9 6 7 6
Manageability 8 7 7 9 9 6 7 7Scalability 6 7 8 8 7 7 7 5
SAN Ready 4 8 8 8 8 6 8 8Upgradeable 4 9 9 8 8 7 7 5
Weighted ScoreEMC
CX300EMC
CX500STK D240
STK D220
Ciprico FibreSt
Adaptec SANbloc
NexSan Ataboy
Initial Cost 72 45 54 63 36 90 90Support Cost 36 36 54 54 45 90 90
Vendor Support 72 72 72 72 64 56 40EDC Experience 42 42 48 48 42 30 36
Performance 64 64 72 64 48 56 48Reliability 81 81 81 81 54 63 54
Manageability 56 56 72 72 48 56 56Scalability 42 48 48 42 42 42 30
SAN Ready 32 32 32 32 24 32 32Upgradeable 36 36 32 32 28 28 20
Total Weighted Score 533 512 565 560 431 543 496
Disk & Tape SystemsDisk & Tape Systems
Additional Reference materialsAdditional Reference materials
• 0403 Storage Matrix.doc
• 040419 SAN Forum.ppt
• 0407 storage overview.ppt
• EDC CR1 Storage Architecuture.ppt