6.0 HP X9000 File Serving Software File System User Guide (TA768-96043, October 2011)

Also note the following:
• Multiple hard links on retained files on the replication source are not replicated. Only the first
hard link encountered by remote replication is replicated, and any additional hard links are
not replicated. (The retainability attributes on the file on the target prevent the creation of any
additional hard links). For this reason, HP strongly recommends that you do not create hard
links on retained files.
• For continuous remote replication, if a file is replicated as retained, but later its retainability
is removed on the source filesystem (using data retention management commands), the new
file’s attributes and any additional changes to that file will fail to replicate. This is because of
the retainability attributes that the file already has on the target, which will cause the filesystem
on the target to prevent remote replication from changing it.
Backup support for data retention
The supported method for backing up and restoring WORM/retained files is to use NDMP with
DMA applications. Other backup methods will back up the file data, but will lose the retention
configuration.
Troubleshooting data retention
Attempts to edit retained files can create empty files
It you attempt to edit a WORM file in the retained state, applications such as the vi editor will be
unable to edit the file, but can leave empty temp files on the file system.
Applications such as vi can appear to update WORM files
If you use an application such as vi to edit a WORM file that is not in the retained state, the file
will be modified, and it will be retained with the default retention period. This is the expected
behavior. The file modification occurs because the editor edits a temporary copy of the file, tries
to rename it to the real file, and when that fails, deletes the original file and then does the rename,
which succeeds (because unretained WORM files are allowed to be deleted).
Cannot enable data retention on a file system with a bad segment
Data retention must be set on all segments of a file system to ensure that all files can be managed
properly. File systems with bad segments cannot be enabled for data retention. If a file system has
a bad segment, evacuate or remove the segment first, and then enable the file system.
Backup support for data retention 125