Object Storage with Swift Cloud storage administration through OpenStack

336 Pages·2014·9.21 MB·English

by  Arnold

OpenStack Swift
Joe Arnold and members of the SwiftStack team
OpenStack Swift
by Joe Arnold and members of the SwiftStack team
Copyright © 2015 SwiftStack, Inc.. All rights reserved.
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October 2014: First Edition
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2014-10-08: First release
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ISBN: 978-1-491-90082-6
[LSI]
Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Part I. Fundamentals and Architecture
1. The Evolution of Storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Storage Needs for Today’s Data 3
The Growth of Data: Exabytes, Hellabytes, and Beyond 4
Requirements for Storing Unstructured Data 4
No One-Size-Fits-All Storage System 5
Object Storage Compared with Other Storage Types 6
A New Storage Architecture: Software-Defined Storage 7
Software-Defined Storage Components 8
Benefits of Software-Defined Storage 9
Why OpenStack Swift? 10
Conclusion 10
2. Meet Swift. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Meet SwiftStack 17
3. Swift’s Data Model and Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Swift Data Model 21
Swift Architecture 24
Server Processes 27
Consistency Processes 29
Locating the Data 30
Ring Basics: Hash Functions 31
Ring Basics: Consistent Hashing Ring 32
The Rings: Modified Consistent Hashing Ring 35
Distribution of Data 37
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Creating and Updating the Rings 37
Creating or Updating Builder Files 37
Rebalancing the Rings 38
Inside the Rings 38
Conclusion 39
4. Swift Basics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Talking to the Cluster: The Swift API 41
Sending a Request 42
Storage URL 42
Authentication 43
HTTP Verbs 43
Authorization and Taking Action 44
Getting a Response 44
Communication Tools 45
Command-Line Interfaces 46
Custom Client Applications 48
Example Scenarios 49
Conclusion 50
Part II. Application Design with Swift
5. Overview of the Swift API. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
What Is an API, Anyway? 53
The CAP Theorem 54
Swift’s Sweet Spot: High Availability, Redundancy, and Throughput 55
Swift API: Background 56
Review of the Hypertext Transfer Protocol (HTTP) 57
Representational State Transfer (REST) 59
Swift, HTTP, and REST 60
Using the Swift API 61
About Your Swift Cluster 61
Authentication 62
Retrieving Data 63
Storing Data 65
Deleting Data 66
Updating Metadata 67
Conclusion 67
6. Swift Client Libraries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Client Libraries 69
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The Authentication Exchange 70
Storage Requests: Basic Usage 71
Client Libraries in Other Languages 74
Ruby 74
PHP 74
Java 75
Storage Requests: Advanced Usage 75
Additional Considerations When Using Python 76
Conclusion 77
7. Advanced API Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Large Objects 79
Object Versioning 81
Object Expiration 81
Temporary URL Middleware (TempURL) 82
Form Post Middleware 82
Custom Metadata 83
PUTting and POSTing Metadata 84
Cross-Origin Resource Sharing (CORS) 84
Swift Cluster Info 85
Range Requests 86
Domain Remap Middleware 86
Static Web Hosting 87
Content-Type Header 88
Bulk Operations Middleware 88
Code Samples 89
Static Large Objects 89
Dynamic Large Objects 90
Object Versioning 91
TempURL (Time-Limited URLs) 92
Form Post 93
Cross-Origin Resource Sharing 94
Custom Metadata 95
Swift Cluster Info 95
Range Requests 96
Domain Remapping 97
Static Web Hosting 98
Content-Type 99
Bulk Upload 99
Bulk Delete 99
Conclusion 100
Table of Contents | v
8. Developing Swift Middleware. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Introduction to WSGI 101
Programming WSGI 103
Streaming and Making Modifications to Data 105
Configuring Middleware Through Paste 106
How to Write Swift Middleware 109
Inside Out 110
Some Simple Examples 111
Doing More in Middleware 112
A Look Back and a Look Forward 117
Conclusion 118
Part III. Installing Swift
9. Installing OpenStack Swift from Source. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Downloading OpenStack Swift 121
Dependencies 122
Installing the Swift CLI (python-swiftclient) 122
Installing Swift 122
Copying in Swift Configuration Files 123
Configuring Swift 123
Adding Drives to Swift 123
Storage Policies 127
Creating the Ring Builder Files 129
Adding Devices to the Builder Files 134
Adding Drives 136
Building the Rings 136
Configuring Swift Logging 137
Creating the Log Configuration File 137
Restarting Rsyslog to Begin Swift Logging 138
Configuring a Proxy Server 138
Setting the Hash Path Prefix and Suffix 138
Starting the Proxy Server 139
Setting up TempAuth Authentication and Authorization with Swift 139
Starting memcached 139
Adding Users to proxy-server.conf 140
Starting the Servers and Restarting the Proxy 140
Account Authentication 141
Verifying Account Access 142
Creating a Container 143
Uploading an Object 144
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Starting the Consistency Processes 144
Configuring rsync 145
Starting the Remaining Consistency Processes 146
Conclusion 146
10. Installing SwiftStack. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
SwiftStack Controller and Node Overview 147
SwiftStack Controller 147
SwiftStack Node 149
Creating a Swift Cluster Using SwiftStack 150
Creating a SwiftStack Controller User 151
Installing the SwiftStack Node Software 151
Claiming a New Node 152
Creating a Cluster 152
Ingesting a Node 153
Enabling a SwiftStack Node 154
Provisioning a SwiftStack Node 154
Adding Swift Users 155
SwiftStack Middleware 156
Deploying to Cluster 156
Creating a Container and Uploading an Object via Web Console 157
Conclusion 158
Part IV. Planning a Swift Deployment
11. Hardware for Swift. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Node Hardware Specifications 162
CPU 162
RAM 165
Drives 167
Cluster Networking 168
Network Cards 169
Outward-Facing Network 170
Cluster-Facing Network 170
Replication Network 171
Out-of-Band Management 171
Other Networking Connections 171
Conclusion 171
12. Planning a Swift Deployment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Your Use Case 173
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System Design 175
How Many Nodes? 175
Tiering Node Services 180
Defining Your Cluster Space 180
Node Naming Conventions 182
Authentication and Authorization 183
Networking 184
Outward-Facing Network 185
Cluster-Facing Network 186
Sample Deployments 188
Small Cluster: Several Nodes 189
Medium-Size Cluster: Multi-Rack 189
Large Cluster: Multi-Region 189
Conclusion 190
13. Authentication and Authorization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
Authentication 191
How Authentication Works 192
Authentication Request 194
Authentication Handling 197
Authentication Response 199
Using the Auth Token in Storage Requests 201
Authorization 201
Authorization Examples 201
How Authorization Works 202
Storage Request Processing 205
Token Verification and Authorization Information Lookup 206
Authorization Callback and Response 206
Authorization and Access Levels 207
Account-Level Access Control 208
Read-Only Access 209
Read-Write Access 209
Admin Access 209
JSON for Account Access Control 209
Container-Level Access Control 210
Container ACL Examples 211
Swift Authentication Systems 212
Keystone 212
TempAuth 212
SWAuth 213
SwiftStack Authentication Systems 214
SwiftStack Auth 214
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