HP OpenVMS Systems Documentation
HP OpenVMS DCL Dictionary
Defines for disk volumes the default protection to be applied to all files on the volume.
Specify the code according to the standard syntax rules described in the HP OpenVMS Guide to System Security. Any attributes not specified are taken from the current default protection.
Note that this attribute is not used when the volume is being used on an OpenVMS system, but is provided to control the process's use of the volume on RSX-11M systems. OpenVMS systems always use the default file protection. Use the SET PROTECTION/DEFAULT command to change the default file protection.
/GROUPUsed in conjunction with the /NOSHARE qualifier to create a group volume. The group volume allows access by system (S), owner (O), and group (G) accessors. The protection is (S:RWCD,O:RWCD,G:RWCD,W).
The owner user identification code (UIC) of the volume defaults to your group number and a member number of 0.
/HEADERS=number-of-headersSpecifies, for disk volumes, the number of file headers to be allocated for the index file. The minimum and default value is 16. The maximum is the value set with the /MAXIMUM_FILES qualifier.
This qualifier is useful when you want to create a number of files and want to streamline the process of allocating space for that number of file headers. If you do not specify this qualifier, the file system dynamically allocates space as it is needed for new headers on the volume.
The /HEADERS qualifier controls how much space is initially allocated to INDEXF.SYS for headers. Each file on a disk requires at least one file header and each header occupies one block within INDEXF.SYS. Files that have many Access Control Entries (ACE) or are very fragmented may use more than one header.
The default value of 16 leaves room for less than 10 files to be created before INDEXF.SYS must extend; therefore, try to estimate the total number of files that will be created on the disk and specify it here. This will improve disk access performance. Overestimating the value may lead to wasted disk space. This value cannot be changed without reinitializing the volume.
INDEXF.SYS is limited as to how many times it may extend. When the map area in its header (where the retrieval pointers are stored) becomes full, file creation fails with the message "SYSTEM-W-HEADERFULL."
/NOHIGHWATERApplies to Files-11 On-Disk Structure Level 2 (ODS-2) and Level 5 (ODS-5) disks only.
Sets the file high-water mark (FHM) volume attribute, which guarantees that users cannot read data that they have not written. You cannot specify the /NOHIGHWATER qualifier for magnetic tape.
The /NOHIGHWATER qualifier disables FHM for a disk volume.
/HOMEBLOCKS=optionApplies to Files-11 On-Disk Structure Level 2 (ODS-2) and Level 5 (ODS-5) disks only.
Specifies where the volume's homeblock and spare copy of the homeblock are placed on disk. The value of option can be one of the following:
/INDEX=positionSpecifies the location of the index file for the volume's directory structure. Possible positions are as follows:
/INTERCHANGESpecifies that the magnetic tape will be used for interchange in a heterogeneous vendor environment. The /INTERCHANGE qualifier omits the ANSI VOL2 labels. Under OpenVMS, the ANSI VOL2 labels contain OpenVMS specific security attributes.
For more information on the /INTERCHANGE qualifier and on magnetic tape labeling and tape interchange, refer to the HP OpenVMS System Manager's Manual, Volume 1: Essentials.
/LABEL=optionDefines characteristics for the magnetic tape volume label, as directed by the included option. The available options are as follows:
/LIMIT[=n]Specifies that the volume should be initialized with volume expansion. n defines the maximum growth potential of the volume in blocks. If no value is specified, the maximum expansion potential is set up.
The maximum value depends on the value specified for /CLUSTER_SIZE. If /CLUSTER_SIZE is 8 (the default when /LIMIT is specified) or more, 1TB of expansion is set up. If the value for /CLUSTER_SIZE is less than 8, the expansion limit is set to 65535*4096*Cluster_value because the maximum size of the bitmap is 65535 blocks. For more information about volume expansion, refer to the HP Volume Shadowing for OpenVMS manual.
The minimum allowed value is the largest of the following values:
If a value less than the minimum is supplied, the value is increased to the minimum. This value is displayed (in blocks) as the "Expansion Size Limit" in the output from a SHOW DEVICE/FULL command.
/MAXIMUM_FILES=nRestricts the maximum number of files that the volume can contain. The /MAXIMUM_FILES qualifier overrides the default value, which is calculated as follows:
(volume size in blocks)/((cluster factor + 1) * 2)
The maximum size you can specify for any volume is as follows:
(volume size in blocks)/(cluster factor + 1)
The minimum value is 0. Note that the maximum can be increased only by reinitializing the volume.
/MEDIA_FORMAT=[NO]COMPACTIONControls whether data records are automatically compacted and blocked together on any device that supports data compaction. Data compaction and record blocking increase the amount of data that can be stored on a single tape cartridge.
Note that once data compaction or noncompaction has been selected for a given cartridge, that same status applies to the entire cartridge.
/OVERRIDE=(option[,...])Requests the INITIALIZE command to ignore data on a magnetic tape volume that protects it from being overwritten. You can specify one or more of the following options:
If you specify only one option, you can omit the parentheses.
To initialize a volume that was initialized previously with the /PROTECTION qualifier, your UIC must match the UIC written on the volume or you must have VOLPRO privilege.
You can initialize a volume previously initialized with /PROTECTION if you have control access.
/OWNER_UIC=uicSpecifies an owner user identification code (UIC) for the volume. The default is your default UIC. Specify the UIC using standard UIC format as described in the HP OpenVMS Guide to System Security.
For magnetic tapes, no UIC is written unless protection on the magnetic tape is specified. If protection is specified, but no owner UIC is specified, your current UIC is assigned ownership of the volume.
Applies the specified protection to the volume:
The default is your default protection. Note that the /GROUP, /SHARE, and /SYSTEM qualifiers can also be used to define protection for disk volumes.
For magnetic tape, the protection code is written to an OpenVMS specific volume label. The system applies only read (R) and write (W) access restrictions; create and delete (D) access are meaningless. Moreover, the system and the owner are always given both read (R) and write (W) access to magnetic tapes, regardless of the protection code you specify.
For more information on specifying protection code, refer to the HP OpenVMS Guide to System Security. Any attributes not specified are taken from the current default protection.
When you specify a protection code for an entire disk volume, the access type E (execute) indicates create access.
/SHADOW=(device_name_1, device_name_2, device_name_3) label (Alpha only)Initializes multiple members of a future shadow set. Initializing multiple members in this way eliminates the requirement of a full copy when you later create a shadow set.
When both the /SHADOW and /ERASE qualifiers are specified, the INITIALIZE command performs the following operations:
HP strongly recommends that you use the /ERASE qualifier. When /ERASE is specified, a merge operation is substantially reduced. However, using /ERASE has two side effects that are important considerations for volume shadowing: the setting of the ERASE volume attribute and the time it takes to initialize a volume using /ERASE.
If /ERASE is specified with /SHADOW, the disks are erased sequentially, which effectively doubles or triples the time it takes for the command to complete. If the disks are large, consider performing multiple, simultaneous INITIALIZE/ERASE commands (without /SHADOW) to erase the disks. Once all of those commands have completed, then execute an INITIALIZE/SHADOW command (without /ERASE).
Once you have initialized your devices using /ERASE and /SHADOW, you can then mount up to three of these devices as members of a new host-based shadow set.
Note that the INITIALIZE/SHADOW command should not be used to initialize a disk to be added to an existing shadow set, as no benefit is gained.
For more information about volume shadowing, refer to the HP Volume Shadowing for OpenVMS manual.
/NOSHAREPermits all categories of access by all categories of ownership. The /NOSHARE qualifier denies access to group (unless the /GROUP qualifier is also specified) and world processes.
/SIZE=nWhen /SIZE=n is specified for a magnetic disk, n specifies the size (in blocks) of the logical volume (the space available for the file system). This allows you to INITIALIZE a disk with a file system size that is less than the physical volume size, which can be useful if you plan to create a shadow set using this disk and a smaller physical disk. The value of n is displayed (in blocks) as "Logical Volume Size" in the output from a SHOW DEVICE/FULL command.
For DECram disks, /SIZEspecifies the size (in blocks) of the disk (device type DT$_RAM_DISK) to be allocated from available memory. The size of the device is created at disk initialization time.
To deallocate space, specify /SIZE=0. All resources specifically allocated to the DECram disk are returned to the system.
Note that n cannot exceed 524,280 blocks either on a VAX system or on versions of DECram prior to Version 2.3. DECram Version 2.3 running on an Alpha system supports up to 67,108,864 blocks, equivalent to 32GB.
/STRUCTURE=levelSpecifies whether the volume should be formatted in Files-11 On-Disk Structure Level 1, 2 (the default), or 5.
Structure Level 1 is incompatible with the /DATA_CHECK and /CLUSTER_SIZE qualifiers. The default protection for a Structure Level 1 disk is full access to system, owner, and group, and read (R) access to all other users.
Note that Alpha does not support Files-11 On-Disk Structure Level 1 disks, and specifying 1 on Alpha results in an error. VAX does not support Structure Level 5 disks, and specifying 5 on VAX results in an error.
Refer to the HP OpenVMS System Manager's Manual, Volume 1: Essentials for more information about Structure Level 5 (ODS-5) disks.
/SYSTEMRequires a system UIC or SYSPRV (system privilege) privilege.
Defines a system volume. The owner UIC defaults to [1,1]. Protection defaults to complete access by all ownership categories, except that only system processes can create top-level directories.
/USER_NAME=nameSpecifies a user name to be associated with the volume. The name must be 1 to 12 alphanumeric characters. The default is your user name.
/NOVERIFIEDIndicates whether the disk has bad block data on it. Use the /NOVERIFIED qualifier to ignore bad block data on the disk. The default is the /VERIFIED qualifier for disks with 4096 blocks or more and the /NOVERIFIED qualifier for disks with less than 4096 blocks.
/VOLUME_CHARACTERISTICS=([[NO]HARDLINKS,] [[NO]ACCESS_DATES[=delta-time]])Applies to Files-11 ODS-5 volumes only.
Enables or disables hardlinks and automatic updates of access dates on ODS-5 volumes.
The default value for delta-time is 1 second, chosen to comply with the "seconds since EPOCH" time interface required by POSIX st_atime . A site can choose a larger delta time to reduce overhead if 1-second granularity is not required.
Note that the NOACCESS_DATES option affects only the node on which the command is issued. Other nodes are not affected by the change until the next time the volume is mounted.
Refer to the Guide to OpenVMS File Applications for additional information.
/WINDOWS=nSpecifies the number of mapping pointers (used to access data in the file) to be allocated for file windows. The value can be an integer in the range of 7 to 80. The default is 7.
Creates or initializes queues. You use this command to create queues and to assign them names and options. The /BATCH qualifier is required to create a batch queue.
Use the INITIALIZE/QUEUE command to create a queue or to change the options of an existing queue that is stopped.