Veritas™ File System Programmer's Reference Guide - Solaris
- Veritas File System software developer's kit
- File Change Log
- About the File Change Log file
- Record types
- File Change Log tunables
- Application programming interface for File Change Log
- API functions
- File Change Log record
- Copying File Change Log records
- Veritas File System and File Change Log upgrade and downgrade
- Reverse path name lookup
- Multi-volume support
- Named data streams
- Veritas File System I/O
- Caching advisories
- Extents
- Thin Reclamation
About multi-volume support
The multi-volume support (MVS) feature lets a VxFS file system use multiple VxVM volumes as underlying storage instead of the traditional single volume per file system. These different volumes can have different characteristics, such as performance, redundancy, or cost, or they could be used to isolate different parts of the file system from each other for performance or administrative purposes.
Administrators and applications can control which files and metadata go into which volumes by using allocation policies. Each file system operation that allocates space examines the applicable allocation policies to see which volumes are specified for that operation. Allocation policies normally only affect new allocations, but there are also interfaces to move existing data to match a new allocation policy.
The following levels of policies can apply to each allocation:
Per-file policies
Per-Storage Checkpoint policies
Per-file-system policies
The most specific allocation policy in effect for a given allocation operation is used.
The MVS APIs fall into the following basic categories:
Manipulation of volumes within a file system
Manipulation of allocation policy definitions
Application of allocation policies
Each of the APIs is also available via options to the fsvoladm(1M) and fsapadm(1M) commands.
See the fsvoladm(1M) and fsapadm(1M) manual pages.