HP Software File Migration Agent Installation and Administration Guide (September 2009)

2 | Overview
Migration
During the migration process, FMA adds FMA-specific metadata to a managed file on a file server and
copies the managed file to one or more archives. FMA supports the following:
Common Internet File System (CIFS), for Windows-based archives
File Transfer Protocol (FTP), for Linux-based archives
HP Integrated Archive Platform (IAP), for IAP archives
Although files can be migrated manually, FMA administrators typically create policies to define the
conditions under which files are migrated. Policies can migrate files based on file name; file age in relation
to creation, modification, or last access time; or a minimum file size. They can exclude files from migration
based on file name or file attributes, such as hidden files. Policies can be run manually or scheduled to run at
regular intervals.
Administrators can apply any number of policies to each managed volume. Policies set in the root folder
apply to all files in the entire volume. Policies set at the folder level are valid for the files in that folder and
its subfolders.
After migration, FMA verifies that the file size and timestamp of a file on the file server and the file on the
archive are identical.
For information about migrating files, see Managed Volumes on page 45.
Release
During the release process, FMA replaces a migrated file on a file server with a stub file. FMA marks this
stub file as offline, which designates files that have remote data.
Although files can be released manually, FMA administrators typically set disk space policies, which are
watermark levels that monitor available disk space on managed volumes. When a managed volume reaches
its high watermark, FMA evaluates the retention policies for the volume and begins releasing files that
match the policy criteria. FMA stops releasing files when it reaches its low watermark. If the critical
watermark is reached, files are released independently of the retention policies. Retention policies are
related to elapsed time since last access or modification to a file. For information about these watermarks,
see
Releasing files using disk space policies on page 48.
Before a file can be released, it must be migrated with at least one valid copy in an archive and it must be
larger than 1024 bytes. Because releasing locks files exclusively, files that cannot be opened exclusively
cannot be released and remain on the file server. Files can also be released according to user-set policies
regarding the number of archived copies existing for each file.
For information about releasing files, see Managed Volumes on page 45.
Recall
When a user or application accesses a released file to read it or write to it, FMA intercepts the read or write
request and retrieves the file data from the archive. If one archive is not available, FMA attempts to find the
file in other archives where the file was also migrated. If FMA cannot recall a file from any of the archives,
it returns an error.
Files can also be manually recalled explicitly by using the FMA command line interface, or by using the
Window Explorer plug-in.
For information about recalling files, see Managed Volumes on page 45.