DMAPI must be enabled individually for each file system.
DMAPI can be enabled for a file system when the file system is created, using the -z yes option on the mmcrfs command. The default is -z no. The setting can be changed when the file system is not mounted anywhere, using the -z yes|no option on the mmchfs command. The setting is persistent.
The current setting can be queried using the -z option on the mmlsfs command.
While DMAPI is disabled for a given file system, no events are generated by file operations of that file system. Any DMAPI function calls referencing that file system fail with an EPERM error.
When mmchfs -z no is used to disable DMAPI, existing event lists, extended attributes, and managed regions in the given file system remain defined, but will be ignored until DMAPI is reenabled. The command mmchfs -z no should be used with caution, since punched holes, if any, are no longer protected by managed regions.
If the file system was created with a release of GPFS earlier than GPFS 1.3, the file system descriptor must be upgraded before attempting to enable DMAPI. The upgrade is done using the -V option on the mmchfs command.
See the GPFS for AIX: Guide and Reference for further information on GPFS commands.