release policies) or at execution of the fsefile --trigger-deletioncommand (deletion policy). The parameters are described in comments inside the FSE configuration file templates.

You need to plan in advance to set the policies according to your environment and to optimize the jobs. The way you set up these policies will affect your FSE implementation’s performance.

Migration

The relevant configuration parameters for the migration policy are specified in the FSE partition configuration file. It is very important that you create a migration policy appropriate for your environment. You should check the default migration policy and adjust settings according to the characteristics of your files.

FSE migration policies are based on file age, wait time for migration, number of files waiting for migration, and the migration volume. Applying these migration parameters in combination creates archival (migration) and retrieval (recall) processes that make the most effective use of the underlying hardware and network infrastructure.

NOTE: You can make redundant copies of the file data during the migration job. For more information, see ”Multiple copying” on page 147.

What is a retried migration?

In case of a failed migration, where files would remain on the migration candidate list and would not be migrated, the migration of such files can be triggered manually from the command line or configured to be run periodically by a cron job (on Linux platform) or scheduled task (on Windows platform).

Use the following command to trigger migration:

fsefile --trigger-migration PartitionName

Adding files to the dirty file list manually

Sometimes it can happen that a file is present on the HSM file system but is not recognized by FSE at a given time. By putting it to the dirty file list the file is recognized and its attributes are preserved. Another file could already be migrated to the FSE medium that has its current status set to unreliable, and is only available for recall if no other copy exists. Such a file can be remigrated to another medium.

In such cases you should manually add files to the dirty file list as follows:

fsefile --migrate FileName

Once the files are added to the dirty file list, they are later moved to the migration candidates list and migrated regularly, according to the migration policy. If the specified file is offline, it will be recalled and then regularly migrated with other files on the list.

Note that zero-size files are always online; they cannot be migrated nor released.

Migration policy parameters

The configuration parameters for migration along with their definition and impact are listed below. The combination of these parameters allows a flexible configuration of migration behavior.

Minimum file age for migration (MinFileAge)

Definition

A period of time after file creation/change during which a file must be left intact to

 

become a migration candidate.

 

 

Impact

You should define the parameter value according to the characteristics of your file data;

 

if your parameter value is too high, for example 5 minutes, and the file is constantly

 

changing (e.g. it is updated every 2 minutes), the file will not be migrated to media.

 

 

HP StorageWorks File System Extender Software user guide 127