Using the FCL file


		< Previous \| TOC \| Index \| Next >

Using the FCL file

VxFS tracks changes to the file system by appending the FCL file with information pertaining to those changes. This enables you to do the following:

Use the FCL to determine the sequence of operations that have been performed on the file system in general or on a specific file after a particular point in time. For instance, an incremental backup application can scan the FCL file to determine which files have been added or modified since the file system was last backed up.
Configure the FCL to track additional information such as file opens, I/O statistics, access information (for example, user ID) along with other changes
You can then use this information to gather the following:
- Space usage statistics to determine how the space usage for different types of data
- Usage profile for the different files on a file system across different users to help determine which data has been recently accessed and by whom
  Note These are new features for the VxFS 5.0 release.

Space usage

You can use the FCL to track space usage when a file system gets close to being full. The FCL file can be searched for recently created files (file creates) or write records to determine newly added files or existing files that have grown recently.

Depending on the application needs, the search can be done on the entire FCL file, or on a portion of the FCL file corresponding to a specific time frame. Additionally, you can look for files created with particular names. For example, if users are downloading *.mp3 files that are taking up too much space, the FCL file can be read to find files created with the name *.mp3.

Full system scan reductions

VxFS creates and logs an FCL record for every update operation performed on an FCL-enabled file system. These operations include: creates, deletes, rename, mode changes, and writes. Therefore, incremental backup applications or applications which maintain an index of a file system based on the file name, file attributes, or content, can avoid a full system scan by reading the FCL file to detect the files that have changed since the previous backup or previous index update.

File history traces

You can trace a file's history by scanning the FCL file and coalescing FCL record sequences for a file. You can also use the related FCL records from a file's creation, attribute changes, write records and the file's deletion to track the file's history.


^ Return to Top	< Previous \| TOC \| Index \| Next >