Technical data

Managing Storage Media
9.11 Managing Disk Space
Example
$ SET VOLUME DUA0:/RETENTION=(15-0:0,20-0:0)
In this example, the command sets the minimum retention period to 15 days and
the maximum to 20 days.
9.12 Using the Analyze/Disk_Structure Utility to Check and Repair
Disks
You can reclaim disk space by using the Analyze/Disk_Structure utility
(ANALYZE/DISK_STRUCTURE) to identify and delete lost files and files marked
for deletion. Use this utility on a regular basis to check disks for inconsistencies
and errors, and to recover lost files.
This utility detects Files-11 Disk Structure (ODS) disk problems that have been
caused by hardware errors, system errors, and user errors. ANALYZE/DISK_
STRUCTURE performs the following tasks:
• Verifies the Files-11 structure on disk volumes
• Reports errors
• Repairs errors when you specify the /REPAIR qualifier
ANALYZE/DISK_STRUCTURE performs the verification of a volume or volume
set in eight distinct stages. During these stages, the utility collects information
used in reporting errors or performing repairs. However, the utility repairs
volumes only when you specify the /REPAIR qualifier.
Compaq recommends that you execute ANALYZE/DISK_STRUCTURE in two
passes:
1. To report all errors
2. With the /REPAIR and /CONFIRM qualifiers to repair selected errors
Directing ANALYZE/DISK_STRUCTURE Output
By default, ANALYZE/DISK_STRUCTURE directs all output to your terminal. By
using the /LIST qualifier, however, you can create a file containing the following
information about each file on the disk:
• File identification (FID)
• File name
• Owner
• Errors associated with the file
The following sections explain ways to use ANALYZE/DISK_STRUCTURE:
Task Section
To report errors (but not repair them) Section 9.12.1
To both report and repair errors Section 9.12.2
To recover lost files Section 9.12.3
To create a disk usage file Section 9.12.5
The OpenVMS System Management Utilities Reference Manual contains
additional information about this utility.
9–70 Managing Storage Media