Viewing snapshots at home

All snapshots at home for RO and LU filesets can be viewed in the cache by setting the afmShowHomeSnapshot parameter to yes. This variable is not applicable for SW and IW filesets.

The home and cache can have different snapshot directories for clarity. If the afmShowHomeSnapshot parameter is changed after fileset creation, the change is reflected in the cache only after IBM Spectrum Scale™ is restarted, or the file system is remounted. However, if the value of afmShowHomeSnapshot parameter is changed from yes to no during the lifetime of a fileset, it continues to show the home snapshots even after a restart, or file system remount.

For RO and LU filesets using NFS, when a lookup is performed from the parent directory of .snapshot directory, the changes at home are not reflected in the cache, as NFS cannot detect the changes in .snapshot. The mtime/ctime parameter of this directory is not modified at home despite snapshots creates or deletes at home. This is not true for RO and LU filesets using GPFS™ backend as the latest snapshot directory gets reflected in cache.