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Storage Area Networks For Dummies®

Book Description

If you’ve been charged with setting up storage area networks for your company, learning how SANs work and managing data storage problems might seem challenging. Storage Area Networks For Dummies, 2nd Edition comes to the rescue with just what you need to know.

Whether you already a bit SAN savvy or you’re a complete novice, here’s the scoop on how SANs save money, how to implement new technologies like data de-duplication, iScsi, and Fibre Channel over Ethernet, how to develop SANs that will aid your company’s disaster recovery plan, and much more. For example, you can:

  • Understand what SANs are, whether you need one, and what you need to build one

  • Learn to use loops, switches, and fabric, and design your SAN for peak performance

  • Create a disaster recovery plan with the appropriate guidelines, remote site, and data copy techniques

  • Discover how to connect or extend SANs and how compression can reduce costs

  • Compare tape and disk backups and network vs. SAN backup to choose the solution you need

  • Find out how data de-duplication makes sense for backup, replication, and retention

  • Follow great troubleshooting tips to help you find and fix a problem

  • Benefit from a glossary of all those pesky acronyms

From the basics for beginners to advanced features like snapshot copies, storage virtualization, and heading off problems before they happen, here’s what you need to do the job with confidence!

Table of Contents

  1. Copyright
  2. About the Authors
  3. Author's Acknowledgments
  4. Introduction
    1. About This Book
    2. Foolish Assumptions
    3. Conventions Used in This Book
    4. How This Book Is Organized
    5. Icons Used in This Book
  5. I. SAN 101
    1. 1. The Storage Area Network
      1. 1.1. Defining a SAN
      2. 1.2. Fiber versus Fibre
      3. 1.3. How a SAN Makes Computing Different
      4. 1.4. Understanding the Benefits of a SAN
      5. 1.5. Finding Out Whether a SAN Is Right for You
        1. 1.5.1. Who should use a SAN?
        2. 1.5.2. Who should not use a SAN?
      6. 1.6. Dissecting a SAN (The Four Ps)
      7. 1.7. The Parts of a SAN
        1. 1.7.1. The host layer
        2. 1.7.2. The fabric layer
        3. 1.7.3. The storage layer
        4. 1.7.4. Storage arrays
      8. 1.8. The SAN Protocols
      9. 1.9. The SAN Players
      10. 1.10. The SAN Platforms
        1. 1.10.1. Applications that benefit from a SAN
        2. 1.10.2. Applications that require a SAN
    2. 2. SAN Building Blocks
      1. 2.1. SAN Components and How They're Used
      2. 2.2. The Host Layer
        1. 2.2.1. Host bus adapters
        2. 2.2.2. Gigabit gadgets: GBICs and GLMs
      3. 2.3. The Fabric Layer
        1. 2.3.1. Understanding storage fabrics
        2. 2.3.2. SAN hubs
        3. 2.3.3. SAN switches
        4. 2.3.4. Data routers
        5. 2.3.5. Cables
        6. 2.3.6. Cable-connector types
        7. 2.3.7. SAN ports and port naming
        8. 2.3.8. Basic SAN port modes of operation
        9. 2.3.9. Protocols used in a Fibre Channel SAN
      4. 2.4. The Storage Layer
        1. 2.4.1. Storage arrays: Storing your data
        2. 2.4.2. Explaining Redundant Array of Inexpensive Disks (RAID)
        3. 2.4.3. RAID benefits
        4. 2.4.4. RAID types
        5. 2.4.5. Logical Unit Numbers (LUNs)
        6. 2.4.6. Understanding storage-array classification
        7. 2.4.7. Modular versus monolithic
        8. 2.4.8. Monolithic (Enterprise)
        9. 2.4.9. Modular (Departmental)
        10. 2.4.10. Why Cache memory makes a difference
    3. 3. What Makes a SAN Go
      1. 3.1. Networking Basics
      2. 3.2. Moving Data at the Speed of Light
      3. 3.3. Bandwidth
      4. 3.4. Fibre Channel Protocols
        1. 3.4.1. The arbitrated loop
        2. 3.4.2. Loop addressing
      5. 3.5. The Switched Fabric
        1. 3.5.1. The fabric protocol
        2. 3.5.2. Fabric addressing
    4. 4. What Makes a SAN Stop
      1. 4.1. Discovering What Causes SAN Problems
      2. 4.2. Preventing Poor SAN Design
        1. 4.2.1. Bandwidth
        2. 4.2.2. Too much distance between components
        3. 4.2.3. Excess latency
        4. 4.2.4. Congestion
        5. 4.2.5. Over-subscription
      3. 4.3. Using the Right Cables in the Right Way
        1. 4.3.1. Avoiding connection issues
        2. 4.3.2. Macro-and micro-bends, and the patch panel pain
        3. 4.3.3. Cable labeling
        4. 4.3.4. Choosing the right host bus adapter for your computer
        5. 4.3.5. Going with a single vendor
        6. 4.3.6. Mixing switch vendors
  6. II. Designing and Building a SAN
    1. 5. Designing the SAN
      1. 5.1. Basic SAN Designs: Understanding the Layers
      2. 5.2. Point-to-Point Topology
      3. 5.3. Arbitrated Loop Topology
        1. 5.3.1. Cascading hubs
        2. 5.3.2. Loop of hubs
        3. 5.3.3. Creating resilient hub networks
        4. 5.3.4. Fault-tolerant loops
      4. 5.4. Switched Fabric Topology
        1. 5.4.1. Types of SAN switches
        2. 5.4.2. Choosing which switches to use
        3. 5.4.3. Using the right bandwidth for the job
        4. 5.4.4. Trunking and what it's used for
      5. 5.5. Basic Fabric Topologies
        1. 5.5.1. Dual switches, the SAN fabric building block
        2. 5.5.2. Loop-of-switches topology
        3. 5.5.3. Meshed fabric topology
        4. 5.5.4. Star topology
        5. 5.5.5. Core-edge topology
      6. 5.6. Understanding Zoning
        1. 5.6.1. The parts of a zone
        2. 5.6.2. Types of zoning
        3. 5.6.3. Zone alias names
      7. 5.7. Initial Switch Setup
        1. 5.7.1. Setting up a Brocade switch
        2. 5.7.2. Setting up an original McData (Brocade) director switch
      8. 5.8. Best Practices — Tips from the Trenches
        1. 5.8.1. When to choose a director-class switch
        2. 5.8.2. Standardize on a single vendor's switches
        3. 5.8.3. Standardize your firmware versions
        4. 5.8.4. Standardize your HBA drivers
        5. 5.8.5. Use unique zone alias names
        6. 5.8.6. Using storage from multiple vendors
        7. 5.8.7. Always use two fabrics
    2. 6. SANs and Disaster Recovery
      1. 6.1. How Much Downtime Can You Afford?
        1. 6.1.1. Gathering the data for a disaster-recovery plan
        2. 6.1.2. Create a detailed plan that meets your requirements
      2. 6.2. Recognizing the Importance of Distance, Bandwidth, and Latency
        1. 6.2.1. Distance
        2. 6.2.2. Bandwidth
        3. 6.2.3. Latency
      3. 6.3. Choosing the Recovery Site
        1. 6.3.1. Existing facility
        2. 6.3.2. Co-location facility
      4. 6.4. Choosing Where to Run the Data Replication Process
        1. 6.4.1. Host-based data replication solutions
        2. 6.4.2. Appliance-based data replication solutions
        3. 6.4.3. Array-based data replication solution
        4. 6.4.4. Shipping tapes as a solution
      5. 6.5. The Importance of Testing
    3. 7. Putting It All Together
      1. 7.1. Building a SAN by Hand
      2. 7.2. The SAN Plan
        1. 7.2.1. Fabric Zoning 101
        2. 7.2.2. LUN security
      3. 7.3. Setting Up the SAN
        1. 7.3.1. Keeping good notes
        2. 7.3.2. Setting up the switches
      4. 7.4. Preparing the Servers
        1. 7.4.1. Loading the driver
        2. 7.4.2. Customizing the HBA card's configuration
        3. 7.4.3. Planning the HBA connections
      5. 7.5. Configuring the Array
        1. 7.5.1. The hardware
        2. 7.5.2. RAID setup
      6. 7.6. Plugging Things In
      7. 7.7. Configuring the Zones
        1. 7.7.1. Mapping the zones first
        2. 7.7.2. I'm zoning out ...
      8. 7.8. Back to the Servers: Did It Work?
        1. 7.8.1. Unix servers
        2. 7.8.2. Windows system
      9. 7.9. iSCSI, You SCSI, We All SCSI
        1. 7.9.1. Initiators and targets
        2. 7.9.2. IQN: iSCSI qualified name
        3. 7.9.3. SCSI Name Service
        4. 7.9.4. Data domains
        5. 7.9.5. Getting started with iSCSI
        6. 7.9.6. Getting serious with iSCSI
      10. 7.10. Data Migration
        1. 7.10.1. Network migration
        2. 7.10.2. Backup/restore migration
        3. 7.10.3. Disk-to-SAN migration
  7. III. Using Advanced SAN Features
    1. 8. Networking SANs
      1. 8.1. Defining a SAN Island
      2. 8.2. Connecting SAN Islands
        1. 8.2.1. Disk/data sharing
        2. 8.2.2. Data copying
      3. 8.3. The Storage WAN, MAN, and SWAN
        1. 8.3.1. Using the network only for storage management
        2. 8.3.2. The storage SWAN
      4. 8.4. Choosing and Using SAN Extenders
      5. 8.5. Choosing the Correct Link for the Job
        1. 8.5.1. IP connections
        2. 8.5.2. OC-type connections
      6. 8.6. Reducing Costs with Compression, Data De-duplication and WAN Tuners
        1. 8.6.1. Compression
        2. 8.6.2. De-duplication
        3. 8.6.3. WAN tuners
      7. 8.7. SAN Connection Protocols
        1. 8.7.1. FCIP: The SAN tunnel
        2. 8.7.2. iFCP: The SAN gateway
      8. 8.8. Stretching the SAN (The Rubber-Band Approach)
      9. 8.9. Using Connected SAN Islands (The Two-Rubber-Bands Approach)
      10. 8.10. Using a SAN as Network Attached Storage
      11. 8.11. iSCSI: An Alternative Method
    2. 9. SAN-Based Backup
      1. 9.1. Understanding Backup
      2. 9.2. Understanding SAN Backup
        1. 9.2.1. The backup window
        2. 9.2.2. Tape drives
        3. 9.2.3. Tape libraries
        4. 9.2.4. Backup policy
      3. 9.3. Choosing a Backup Solution
        1. 9.3.1. Integrated tape drive in each server
        2. 9.3.2. Backup over a corporate LAN to a tape drive connected to an independent backup server
        3. 9.3.3. Backup over corporate network to robotic tape library connected to an independent backup server
        4. 9.3.4. LAN-less backup to shared tape library over SAN
        5. 9.3.5. Serverless backup to shared tape library through SAN
        6. 9.3.6. Disk-to-disk backup
        7. 9.3.7. Image copy and snapshots in the SAN
        8. 9.3.8. SAN data replication/remote backup
      4. 9.4. Determining How Long a Backup Will Take
        1. 9.4.1. Determining backup speeds
        2. 9.4.2. The formula for backup
    3. 10. Mirror, Mirror: Point-in-Time Copies
      1. 10.1. The Uses of Point-in-Time Technology
        1. 10.1.1. Make backups
        2. 10.1.2. Make corruption-recovery images
        3. 10.1.3. Save space
        4. 10.1.4. The possibilities are endless
      2. 10.2. Complete versus Metadata Copies
      3. 10.3. Which PiT Type Should You Use?
      4. 10.4. Creating a PiT Copy
      5. 10.5. Managing Your Point-in-Time Copies
        1. 10.5.1. Pair up your volumes
        2. 10.5.2. Create the pairs
        3. 10.5.3. Splitting the mirror, snapping a copy
        4. 10.5.4. Doing a resync: Refresh and restore
        5. 10.5.5. I need my data now!
        6. 10.5.6. Using a PiT copy
      6. 10.6. The Finer Points of PiT
        1. 10.6.1. Guideline #1: Understand when to snap a copy
        2. 10.6.2. Guideline #2: Keep your PiT pairs separated
        3. 10.6.3. Guideline #3: Use the right disk storage for PiT copies
        4. 10.6.4. Questions to ask your SAN vendors
  8. IV. SAN Management and Troubleshooting
    1. 11. Approaches to SAN Management
      1. 11.1. Management: From Simple Networking to SANs
      2. 11.2. SAN Management from the Ground Up
        1. 11.2.1. Start small; think big
        2. 11.2.2. Documentation is key
      3. 11.3. Cable Management: Spaghetti, Anyone?
        1. 11.3.1. Physical cable management
        2. 11.3.2. Logical cable management
      4. 11.4. Labeling Your Cables
        1. 11.4.1. Data center coordinate system
        2. 11.4.2. Standard naming convention
        3. 11.4.3. Documenting the cable arrangements
      5. 11.5. Using a SAN Management Framework
        1. 11.5.1. Working with SAN management software
        2. 11.5.2. Communicating in a common language
        3. 11.5.3. Speaking the language yourself
        4. 11.5.4. Putting everything together
      6. 11.6. What SAN Management Gives You
        1. 11.6.1. A bird's-eye view of your network
        2. 11.6.2. Agent-based management
        3. 11.6.3. Health monitoring
        4. 11.6.4. Records of events
        5. 11.6.5. Change management
        6. 11.6.6. Predictions of problems
      7. 11.7. Streamlining SAN Administration
        1. 11.7.1. Step-by-step administration
        2. 11.7.2. Using a framework
      8. 11.8. Automating Your System: "SAN? Do You Read Me, SAN?"
        1. 11.8.1. Backing up
        2. 11.8.2. Managing database storage
      9. 11.9. Providing a Service Level Agreement
        1. 11.9.1. Simple versus complex SLAs
        2. 11.9.2. Setting service levels
      10. 11.10. Building a Storage Management Team
        1. 11.10.1. SAN architects
        2. 11.10.2. SAN engineers
        3. 11.10.3. Monitoring team
        4. 11.10.4. SLA and performance specialists
        5. 11.10.5. Provisioning staff
        6. 11.10.6. Planning for the future
        7. 11.10.7. Common responsibilities
    2. 12. Troubleshooting SANs
      1. 12.1. The Best Method: Prevention
      2. 12.2. Troubleshooting Methodology
        1. 12.2.1. Go with what you know
        2. 12.2.2. Elementary, my dear Watson
        3. 12.2.3. Didn't read the manual, did you?
        4. 12.2.4. Build a golden configuration
      3. 12.3. Typical Problem Types
        1. 12.3.1. Obvious problems
        2. 12.3.2. Phantom problems
        3. 12.3.3. Continuous problems
        4. 12.3.4. Catastrophic problems
      4. 12.4. Example Scenarios
        1. 12.4.1. Scenario #1
        2. 12.4.2. Scenario #2
        3. 12.4.3. Scenario #3
  9. V. Understanding the Cool Stuff
    1. 13. Using Data De-Duplication to Lighten the Load
      1. 13.1. Understanding Data De-Duplication
        1. 13.1.1. Benefits of data de-duplication
        2. 13.1.2. How de-duplication works
      2. 13.2. Data De-Duplication in the Datacenter
        1. 13.2.1. The de-duplication vendors
        2. 13.2.2. How data gets de-duplicated
        3. 13.2.3. In-band versus out-of-band data de-duplication
      3. 13.3. Using Data De-Duplication in a SAN
        1. 13.3.1. Files: Honey, I shrunk the files
        2. 13.3.2. Blocks: Been there, stored that
        3. 13.3.3. What about hash collisions?
      4. 13.4. Why Data De-Duplication Is Important
      5. 13.5. When to Use Data De-Dupe (And When Not To)
        1. 13.5.1. Applications for which data de-duplication makes sense
        2. 13.5.2. Applications for which data de-duplication doesn't make sense
      6. 13.6. De-Duplication in Action
    2. 14. Continuous Data Protection
      1. 14.1. Understanding What Continuous Data Protection Is
      2. 14.2. How CDP Makes Storage Work Like a Database
        1. 14.2.1. CDP data journaling
        2. 14.2.2. Splitting the writes
        3. 14.2.3. CDP makes everything different
        4. 14.2.4. Sizing a CDP journal
      3. 14.3. Best Practices for Storage When Configuring CDP Solutions
      4. 14.4. The Truth about Near CDP and True CDP Solutions
        1. 14.4.1. Example 1: Recovering a database with traditional backup
        2. 14.4.2. Example 2: Recovering a database from a snapshot
        3. 14.4.3. Example 3: Recovering a database using near CDP
        4. 14.4.4. Example 4: Recovering a database using true CDP
      5. 14.5. CDP versus Snapshots
      6. 14.6. Using CDP to Eliminate Backups
      7. 14.7. Using CDP to Simplify Recovery and Reduce Costs
      8. 14.8. Knowing Your CDP Vendor
    3. 15. Everything You Ever Wanted to Know about Virtualization
      1. 15.1. Understanding What Virtualization Is
      2. 15.2. Exploring the Types of Virtualization
      3. 15.3. Implementing Virtualization in a Datacenter
        1. 15.3.1. Server virtualization
        2. 15.3.2. Storage virtualization
      4. 15.4. In-Band versus Out-of-Band Virtualization
        1. 15.4.1. In-band virtualization
        2. 15.4.2. Out-of-band virtualization
      5. 15.5. The Virtualization Vendors and Where They Play
        1. 15.5.1. Host-based storage virtualization vendors
        2. 15.5.2. Fabric-based virtualization storage vendors
        3. 15.5.3. Storage-array-based virtualization
  10. VI. The Part of Tens
    1. 16. Ten Reasons to Use a SAN
      1. 16.1. You Want Better Disk Utilization
      2. 16.2. You Need a Good Disaster Recovery Solution for Multiple Applications
      3. 16.3. You Need Better Availability for Your Applications
      4. 16.4. You Need More Storage Room
      5. 16.5. Backup Is Taking Too Long
      6. 16.6. You're Focusing on Server and Storage Consolidation
      7. 16.7. You've Been Tasked to Save Your Company Money
      8. 16.8. You Need to Manage Storage for Many Locations from a Central Site
      9. 16.9. You Need to Decrease IT Management Costs
      10. 16.10. You Need Better Performance for Your Applications
    2. 17. Ten Reasons NOT to Use a SAN
      1. 17.1. You Need Larger File Servers
      2. 17.2. You Only Have a Few Inexpensive Servers
      3. 17.3. You Want to Save Your Company Money This Year
      4. 17.4. You Want to Use the Latest and Greatest Solutions Available
      5. 17.5. You Need a Disaster-Recovery Solution for a Single Application
      6. 17.6. You Want a SAN but Don't Have the Budget
      7. 17.7. You Use Gigabit Ethernet on Your LAN
      8. 17.8. Everything Already Runs Fine
      9. 17.9. You Need to Back Up Multiple Remote Offices over Slow Links
      10. 17.10. You Need to Replicate Your Data for Disaster Recovery but Can't Afford Fast WAN Connections
  11. Outsourcing SAN Solutions