STORAGE ARCHITECTURE/ MASTER): Where IP and FC Storage Fit in Your Enterprise Randy Kerns Senior Partner The Evaluator Group.
Download ReportTranscript STORAGE ARCHITECTURE/ MASTER): Where IP and FC Storage Fit in Your Enterprise Randy Kerns Senior Partner The Evaluator Group.
STORAGE ARCHITECTURE/ MASTER): Where IP and FC Storage Fit in Your Enterprise
Randy Kerns Senior Partner The Evaluator Group
Agenda
Storage Connection
• •
Fibre Channel IP
NAS
iSCSI
Planning
Usage
Storage connection
Fibre Channel
•
Used in Storage Area Networks (SAN)
Enterprise datacenter environments
In SMB – primarily with packaged solution “SAN in a Box”
• •
Direct connection from servers to storage systems Used in storage systems for drive connections
Fibre channel
Targeted at block-level I/O for high performance
Heterogeneous storage and server attachment
Nearly unlimited scaling of storage
•
capacity
•
performance (bandwidth)
Centralized administration
Shared resources – pooling of devices
Enterprise class capabilities – RAS, capacity planning, business continuity
Fibre channel (2)
Clients Local Area Network Servers SAN JBOD
Disk array
ATL
Storage connection
Network Attached Storage (NAS)
•
Special purpose device to provide remote file system to other servers on the network
•
Usually a kernel or thin server that supports NFS, CIFS, HTTP and FTP
some implement standard server and call it NAS
single purpose devices are called appliances
•
Utilizes IP for connection protocol and UDP or TCP
NAS
Simplicity – easy to install and administer
High Availability – many NAS devices are fault tolerant and support internal failover
Scalability – most NAS devices can scale in capacity and performance up to a point (upper limit)
Connectivity – utilizes standard network infrastructures (typically Ethernet) and supports multiple connections
NAS (2)
Access – done with NFS and CIFS
Data Sharing – a basic function of NAS for files
Cost – significant competition has driven costs down. Many offerings from wide range of vendors
Backup – beginning to see backup over SANs, but many have integrated backup devices to avoid LAN usage
NAS (3)
Workstation Workstation
Server
NAS
Storage
Disk array Host Tower box
LAN
I/O Requests for for File I/O using NFS, CIFS Server owns storage device and does block level I/O
0/0
1.
2.
Do you have NAS installed in:
30% 30%
Departments in larger companies
20% 20%
Enterprise Data Center 3.
Small to mid-size business 4.
None
1 2 3 4
Storage connection
iSCSI – Internet SCSI
• • • Use of SCSI commands over IP Target is to provide block I/O using Ethernet infrastructure No mechanism in Ethernet/IP to allow for command-response structure of SCSI SCSI is block oriented storage interface Both an interface and a protocol • Ethernet / IP has network characteristics No flow control – drops packets on congestion Packet size is limited – get smaller as contention increases iSCSI attempts to work within these constraints
iSCSI mapping over IP
iSCSI TCP IP
Open Systems Interconnect Model Application Presentation Session Transport Network Data Link Physical
Abstraction of network for access by application. The application will do a read or write operation either to a device or a file.
Data transformation occurs to present in a uniform manner. This is implemented with the application layer.
iSCSI is established as an application session to map SCSI on top of TCP Responsible for end-to-end delivery utilizing two services: connection oriented (TCP) and connectionless (UDP).
Routing of data packets between systems with intermediate systems. Usual protocol implement for this is IP (Internet Protocol).
Data transfer across medium including error checking, forwarding and retransmission requests. Example is Ethernet.
Type of communication medium (copper, fibre, RF), signal modulation, bit encoding
iSCSI – Encapsulation
Ethernet Header IP Header TCP Header iSCSI Header Data Up to 1,450 Bytes CRC
Delivery of iSCSI Protocol Data Unit (PDU) to contain state and control information for SCSI Reliable transport software information for delivery and ordering. Internet Protocol for routing through a network Physical network interface and control for Ethernet
iSCSI – Encapsulation mapping SCSI Comand Descriptor Block and Data Header iSCSI PDU Data Header iSCSI PDU Data Header iSCSI PDU Data IP Packet IP Packet IP Packet IP Packet IP Packet No Natural Alignment for Encapsulation
iSCSI usage
IP SAN Using iSCSI Servers
Ethernet
Ethernet Switch
Network 10/100 Gig-E Sonet/SDH ATM
Storage System Remote Site
iSCSI usage (2)
iSCSI Connection for Stranded Servers Servers FC to IP Routers Fibre Channel Fabric Storage Systems Stranded Servers
0/0
If you plan on using iSCSI, will it be for:
40%
1.
An IP SAN
30% 30%
2.
Connect stranded servers 3.
Both
1 2 3
Planning
Understand requirements
• • •
Look at performance, security, cost, availability Understand administrative issues and needs Look at needs in the future
Decide which solutions fit the requirements
• •
Technology characteristics Consider the economics
Administrative costs
Expansion costs
Device / infrastructure costs
Usage
Enterprise DataCenter market
•
Majority of companies have deployed FC SANs
> 80% in some form
> Half of storage in storage network
•
Most have single switch/director vendor for specific SAN
Want to manage only one type
•
Many have only one storage vendor per SAN
Because that’s the way salesmen sold it
•
NAS Gateways are seeing deployments
Major vendors offering gateways
New challenge for storage administrators
Establishes presence for NAS in Enterprise Datacenters
•
Customer focus is now on storage management
Usage (2)
Small to mid-size business
•
FC SAN is usually packaged “SAN in a box” solution
No storage professionals to implement or manage a SAN
Percentage-wise, a small amount of deployment
•
IP SANs are early in deployment
Typically in very cost-sensitive environments
Still storage administration to do
•
NAS is very successful in SMB market
Also departmental and workgroup
Fits well with requirements
•
Market open for many types of solutions
Large and growing market with varying requirements
Summary
Choose wisely
• • • •
Performance requirement – FC Minimal administration and file I/O – choose NAS Connect stranded server cheaply – iSCSI Block I/O with minimal cost and not a high performance requirement – iSCSI or packaged FC solution