Veritas™ File System 5.0.1 Administrator's Guide

Chapter 4 VxFS I/O Overview ............................................................... 69
About VxFS I/O ............................................................................ 69
Buffered and Direct I/O ................................................................. 70
Direct I/O ............................................................................. 70
Unbuffered I/O ...................................................................... 71
Data synchronous I/O ............................................................. 71
Concurrent I/O ............................................................................ 72
Cache advisories .......................................................................... 73
Freezing and thawing a file system .................................................. 73
Getting the I/O size ...................................................................... 74
Chapter 5 Online backup using file system snapshots .................. 75
About snapshot file systems ........................................................... 75
Snapshot file system backups ......................................................... 76
Creating a snapshot file system ...................................................... 77
Backup examples ......................................................................... 77
Snapshot file system performance .................................................. 78
Differences Between Snapshots and Storage Checkpoints .................... 79
About snapshot file system disk structure ........................................ 79
How a snapshot file system works ................................................... 80
Chapter 6 Storage Checkpoints .......................................................... 83
About Storage Checkpoints ............................................................ 83
How Storage Checkpoints differ from snapshots .......................... 84
How a Storage Checkpoint works .................................................... 85
Copy-on-write ....................................................................... 87
Types of Storage Checkpoints ......................................................... 88
Data Storage Checkpoints ........................................................ 88
nodata Storage Checkpoints ..................................................... 88
Removable Storage Checkpoints ............................................... 89
Non-mountable Storage Checkpoints ......................................... 89
Storage Checkpoint administration ................................................. 90
Creating a Storage Checkpoint .................................................. 91
Removing a Storage Checkpoint ................................................ 92
Accessing a Storage Checkpoint ................................................ 92
Converting a data Storage Checkpoint to a nodata Storage
Checkpoint ..................................................................... 94
Space management considerations ................................................ 101
Restoring a file system from a Storage Checkpoint ........................... 102
Restoring a file from a Storage Checkpoint ................................ 102
Storage Checkpoint quotas ........................................................... 107
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