Disk Quota

Disk quotas are device-specific, not universal. Any disk may have quotas enabled. If enabled, each account's disk space usage on that disk is compared with the user's disk quota, and the account is prohibited from using more than this allocated limit. Disk quotas are managed with SYSMAN DISKQUOTA. The quota database is created with the subcommand CREATE, and accounts are added with the subcommand MODIFY. For instance, to establish a disk with quota enabled—and all users of the disk must have a quota defined—the following command is used:

     $ SYSMAN DISKQUOTA CREATE/DEVICE=disk_name 

This command is described in the OpenVMS System Manager's Manual, Chapter 9. SYSMAN is fully described in the OpenVMS System Management Utilities Reference Manual, Chapter 21.

Next, the manager would define a disk quota for the specific user:

     $ SYSMAN DISKQUOTA ADD [DMILLER]/DEVICE=FACULTY -     _$ /PERMQUOTA=150000/OVERDRAFT=100 

This command was illustrated previously as well. The user can monitor personal disk usage with the simple command, shown as follows:

     $ show quo       User [DMILLER] has 90821 blocks used, 59179 available,       of 150000 authorized and permitted overdraft of 100 blocks on FACULTY 

Likewise, the manager can monitor disk quota, as in the following example:

     $ mcr sysman     SYSMAN> diskquota show [dmiller] /device=faculty     disk quota statistics on device EAGLE$DKBO:[FACULTY.] --     Node LOON          UIC                  Usage        Permanent Quota   Overdraft Limit     [DMILLER]                 90821        150000            100 

Notice that disk quota is not directly tied to user authorization and needs to be managed separately. The disk quota database is maintained on the target disk in [000000]QUOTA.SYS. It is also possible to add disk quota management to a disk at any time (i.e., after directories have been established). This is done with the following command:

     $ SYSMAN DISKQUOTA REBUILD/DEVICE=disk_name