Technical data

Managing Storage Media
9.12 Using the Analyze/Disk_Structure Utility to Check and Repair Disks
For complete descriptions of all errors and recommended actions, refer to the
OpenVMS Command Definition, Librarian, and Message Utilities Manual.
9.12.3 Recovering Lost Files
A lost file is not linked to a directory. Under normal circumstances, files are
not lost. However, files occasionally lose their directory links because of disk
corruption, hardware problems, or user error.
For example, in cleaning up files and directories, you might inadvertently delete
directories that still point to files. When you delete a directory file (a file with the
file type .DIR) without first deleting its subordinate files, the files referred to by
that directory become lost files. Though lost, these files remain on the disk and
consume space.
Use ANALYZE/DISK_STRUCTURE periodically to check for disk structure errors
such as lost files on the disk. When you run ANALYZE/DISK_STRUCTURE
specifying the /REPAIR qualifier, the utility places lost files in disk:[SYSLOST]
and issues a message about each file, shown in the example that follows. (Refer
to the OpenVMS System Management Utilities Reference Manual for more
information.)
Example
$ ANALYZE/DISK_STRUCTURE/REPAIR/CONFIRM DDA0:
The command in this example analyzes and repairs all errors and lost files on the
DDA0: device.
If it discovers lost files on your disk, ANALYZE/DISK_STRUCTURE issues
messages similar to the following:
%VERIFY-W-LOSTHEADER, file (16,1,1) []X.X;1
not found in a directory
%VERIFY-W-LOSTHEADER, file (17,1,1) []Y.Y;1
not found in a directory
%VERIFY-W-LOSTHEADER, file (18,1,1) []Z.Z;1
not found in a directory
%VERIFY-W-LOSTHEADER, file (19,1,1) []X.X;2
not found in a directory
%VERIFY-W-LOSTHEADER, file (20,1,1) []Y.Y;2
not found in a directory
%VERIFY-W-LOSTHEADER, file (21,1,1) []Z.;1
not found in a directory
%VERIFY-W-LOSTHEADER, file (22,1,1) []Z.;2
not found in a directory
%VERIFY-W-LOSTHEADER, file (23,1,1) LOGIN.COM;163
not found in a directory
%VERIFY-W-LOSTHEADER, file (24,1,1) MANYACL.COM;1
not found in a directory
All lost files in this example are automatically moved to DDA0:[SYSLOST].
Another opportunity to check for lost files on your system is during a backup
operation. See Section 11.13.3 for details.
9–72 Managing Storage Media