Serial Attached SCSI SAS - PowerPoint PPT Presentation

1 / 24
About This Presentation
Title:

Serial Attached SCSI SAS

Description:

SATA-Only RAID Solutions. Direct Connect, Backplane, and Multi-Lane. X4 ML. ONLY. LSI Proprietary ... connections between a HBA/RAID SAS controller and a SAS ... – PowerPoint PPT presentation

Number of Views:1689
Avg rating:5.0/5.0
Slides: 25
Provided by: lsil
Category:
Tags: sas | scsi | attached | raid | serial

less

Transcript and Presenter's Notes

Title: Serial Attached SCSI SAS


1
Serial Attached SCSI (SAS) SATA II Overview
2
Why Should You Learn about SAS?
  • SAS is a scalable, flexible, cost effective, high
    performance storage interface
  • SAS adds new capabilities to SCSI
  • If you have existing SCSI customers, they will be
    excited about SAS
  • SAS brings new capabilities to SATA

3
The Emergence of Serial Attached SCSI (SAS)
  • Newest Storage Interface for Direct Attach
    Storage (DAS)
  • SAS Is the Next Generation of SCSI
  • Supported by the same ANSI T10 Standards
    Committee
  • Successor to Ultra320 SCSI on Industry Roadmap
  • Leverages SCSI Expertise
  • Significant Performance Feature Set Enhancements

Source SCSI Trade Association Jan 2004
4
SATA vs. Enterprise SATA Hard Drives
Compliments Of
5
Enterprise Server Disk Drive Market Outlook
  • Predict 70 of Disc sold for Enterprise Server
    will be SAS/SATA
  • Success of SAS as new Direct Attach Storage
    replacement is well underway
  • Analysts predict market will drive consolidation
    in PB1-PB6, capping FC growth.

Source IDC
6
SAS is Compatible with SATA II!
  • Feature SAS controllers can talk to SATA or SAS
    HD Drives
  • SAS HDD - Used When Performance Reliability are
    Critical
  • SATA HDD - Used When Capacity Cost Are Most
    Important
  • SAS SATA HDD - Can be Mixed in Single System
  • Benefit Server, Workstation, and External
    Enclosures Can be Standardized on SAS. This
    will
  • Reduce Component Qualification Costs
  • Reduce Enclosure SKUs and Inventories
  • Provide cost parity with comparable SATA
    solutions

7
Mechanical Interoperability
SAS HDD SATA HDD
Dual Ports
Single Ports
One Tiny Difference
8
Learning Check
Top 5 OEMS
A primary advantage of SAS controllers is
A Their ability to communicate with SAS and
SATA HDDs B Their ability to communicate with
SAS and FC HDDs C Their ability to communicate
with SAS HDDs only D All of the above
9
New Terms
  • 1) SATA Architected, SATA Populated (SATA)
  • A system that contains SATA Controllers and SATA
    HDDs
  • Low cost, GREAT for certain markets (i.e.
    streaming, archive)
  • 2) SAS Architected, SAS Populated (SAS)
  • A system that contains SAS controllers, SAS HDD,
    and optionally SAS expanders
  • X3 cost on HDD, top notch performance for IOP
    intensive applications
  • 3) SAS Architected, SATA Populated (SAS/SATA)
  • A system that contains SAS controllers, SATA HDD,
    and optionally SAS expanders
  • This allows the creation of sophisticated
    topologies with low cost SATA HDD

10
The Power of Serial Interfaces
11
SAS - SCSI on Steroids! (Improvements Over SCSI)
12
SAS SATA - The New Paradigm(SAS Increases the
Performance and Versatility of SATA based systems)
13
HDD Connectivity Technology Comparison
SAS adds FC Capabilities
Significant Differences Exist
Fibre Channel
SAS
SATA II

Half-duplex
?
Performance
Full-duplex with Link Aggregation
Full Duplex

3.0 Gb/s
3.0 Gb/s Introduction 6.0 Gb/s in 2007
2.0 Gb/s 4 Gb/s in 2005
Connectivity
gt 6 m internal and external cables
1 m internal cable
15 m external cable (Copper)
?
Multipliers 15 HDD max

Expanders gt128 devices
?
127 devices FC-AL 16 Million Fabric

?
Availability
Dual-port HDDs
Single-port HDDs
Dual-port HDDs

?
Multi-initiator
Single-host
Multi-initiator

?
Driver Model
Software transparent with Parallel SCSI
Software transparent with Parallel ATA
Software transparent with Parallel SCSI
14
Learning Check
True or False?
SAS hard drives (HDDs) will eventually displace
SATA hard drives in the marketplace?
15
SATA-Only RAID SolutionsDirect Connect,
Backplane, and Multi-Lane
ONLY
X4 ML
Direct Connect via Backplane
Multi Lane
Direct Connect
16
SAS/SATA RAID SolutionsIdentical to SATA PLUS
OR
X4 ML
Direct Connect via Backplane
Multi Lane
Direct Connect
17
. . What SATA Does Not Have - SAS Expanders
  • Expanders are a piece of silicon, most commonly
    found on a backplane into which HDDs plug
  • Expanders allow 1 or more SAS controller ports to
    fan out to many HDDs
  • Expanders supports SAS or SATA Disc Drives
  • Mix and Match!!

4 Ports 12 HDDs!
OR
18
SAS Expanders Wide Ports Are Key!!
  • SAS Wide Ports are Unique in Storage
  • No SCSI, SATA, or FC equivalent
  • Nearest equivalent might be Ethernet Trunking
  • Wide ports are used to aggregate bandwidth
  • One or more SAS ports can be used to talk with
    many HDDs
  • Definition A wide port is a single logical
    connection (i.e. port) between two devices built
    from 1-4 physical wires (i.e. links).
  • Typical usage redundant connections between a
    HBA/RAID SAS controller and a SAS expander are
    configured as a wide port
  • Wide ports are transparent to the host/OS and HDDs

19
Expanders and Scalability The promise of SAS
OR
10 HDD 4 Ports!!
SAS Expanders brings the opportunity for the OEM
and System Builder to create a truly unique
product offering by scaling the number of SATA
drives way beyond typical applications..
20
SAS RAID More Flexibility/Scalability than SATA
RAID
Direct Connect OR Multilane
X4 ML
X4 ML
X4 ML
X4 ML
16 Port SATA RAID 16 HDD
8 Port SAS RAID 40 HDD
  • Flexibility for SATA and SAS Hard Drives
  • Scalability using 8 Ports to 36 HDDs
  • Limited Outside the Box Options
  • Limited to 16 SATA Hard Drives

21
Scalability Only SAS does this!!
OR
22
Key Takeaways
  • SAS adds new features to SCSI
  • SAS brings new capabilities to SATA
  • SAS provides
  • Flexibility
  • Scalability
  • Cost-effective tiered storage solutions
  • High performance for SAS and SATA systems

23
The SAS Infrastructure
24
(No Transcript)
Write a Comment
User Comments (0)
About PowerShow.com