File migration eligibility

A file must meet several criteria to be eligible for migration.

A file is eligible for automatic migration, selective migration, or premigration when it meets the following criteria:

• The file is a regular file. Character special files, block special files, FIFO special files (named pipe files), or directories are not migrated.
• The file is a resident or premigrated file on a file system for which space management is active.
• The file is not excluded from space management in your include-exclude options file.
• To be eligible for migration, a file must satisfy all of the following size criteria:
  • The file logical size is larger than the value of the stubsize option.
  • The space that a file occupies is at least as great as the value of the minmigfilesize option.
  Restriction: The size criteria do not apply for premigration.
• The file meets management class criteria.
• A file in a multiple-server environment that is coupled with a server can be migrated to only that server.
• The file is more than 2 minutes old. You can migrate files that are less than 2 minutes old if you set hsmenableimmediatemigrate = yes.

You can migrate a file in a set of hard linked files. The file must not be excluded from space management and must be assigned to a management class that allows automatic or selective migration.