The e-mail address to receive output from administrative tasks.

administrative directories

See DMF administrative directories.


A floating-point constant and floating-point multiplier used to calculate the weight given to a file's age (for MSP/VG user filesystem).


The always on region, a section of COPAN MAID disk that will always be spinning and available for access. This region is not used by DMF.

base object

The configuration file object that defines pathname and file size parameters necessary for DMF operation.

bit-file identifier

(BFID) A unique identifier, assigned to each file during the migration process, that links a migrated file to its data on alternate media.


Physical unit of I/O to and from media, usually tape. The size of a block is determined by the type of device being written. A block is accompanied by a header identifying the chunk number, zone number, and its position within the chunk.


The directory in which the VG stores chunks while merging them from sparse volumes.


The single VG or one or more MGs to be used as a fast-mount cache.


That portion of a user file that fits on the current media volume. Most small files are written as single chunks. When a migrated file cannot fit onto a single volume, the file is split into chunks.

configuration file object

A series of parameter definitions in the DMF configuration file that controls the way in which DMF operates. By changing the parameters associated with objects, you can modify the behavior of DMF.

configuration parameter

A string in the DMF configuration file that defines a part of a configuration object. By changing the values associated with these parameters, you can modify the behavior of DMF. The parameter serves as the name of the line. Some parameters are reserved words, some are supplied by the site.

configuration stanza

A sequence of configuration parameters that define a configuration object.


Power-efficient long-term data storage solution based on an enterprise massive array of idle disks (MAID) platform.


Power-efficient long-term data storage solution based on an enterprise MAID platform using a virtual tape library (VTL).


A parameter that specifies that the fourth character of the volume serial number (VSN) indicates the RAID in the COPAN VTL or COPAN MAID that contains the VSN. This specification applies for all VSNs in this library server.


A program that is run automatically by the system for a specific purpose.

daemon database

A database maintained by the DMF daemon.


One or more directories into which a copy of the DMF databases will be placed.


See drive group.

DMF administrative directories

The directories in which DMF stores databases, log files, journal files, and temporary files. The DMF configuration file specifies these directories using the following parameters:


DMF daemon

The program that accepts requests to migrate data, communicates with the operating system kernel in order to maintain a file's migration state, determines the destination of migrated data, and requests the return of offline copies.

DMF server

A node running the required DMF server software that provides DMF administration, configuration, and data mover functionality. (When using the Parallel Data Mover Option, data mover functionality is optional on the DMF server.)


A hardware device that reads and writes data.

drive group

One of the components of an LS. The drive group is responsible for the management of a group of interchangeable drives located in the library. These drives can be used by multiple VGs and by non-DMF processes, such as backups and interactive users. However, in the latter cases, the drive group has no management involvement; the OpenVault mounting service is responsible for ensuring that these possibly competing uses of the drives do not interfere with each other. The main tasks of the drive group are to monitor I/O for errors, to attempt to classify them (as volume, drive, or mounting service problems), and to take preventive action.

dual-state file

A file whose data resides both online and offline.


One or more filesystems to back up. If not specified, the tasks will back up all the DMF-managed user filesystems configured in the configuration file.


One or more directories in which to place a copy of disk-based backups.

fast-mount cache

A migration target with fast mount/position characteristics (such as COPAN MAID) that is used in conjunction with another permanent storage target (such as physical tape). Data copies are placed on the fast-mount cache and the permanent storage target at the time of initial migration.


An inode and its associated data blocks; an empty file has an inode but no data blocks.


The age (in days) of a file that must not be deleted from the fast-mount cache.


The specific scratch MOVE_FS directory to be used when moving files to be retained in the fast-mount cache.


The minimum percentage of free volumes in the COPAN MAID or COPAN VTL fast-mount cache that will cause run_fmc_free.shto begin freeing full volumes in order to meet the percentage set for FREE_VOLUME_TARGET.


The percentage of volumes in the COPAN MAID or COPAN VTL fast-mount cache that tries to free when the FREE_VOLUME_MINIMUM threshold is reached.


High availability.


The base pathname for directories in which DMF databases and related files reside.


The portion of a file that contains the bit-file identifier, the state field, and the data pointers.


Library control program.

library server

A daemon-like process by which data blocks are copied onto a volume and that maintains the location of the migrated data. An LS can be configured to contain one or more drive groups. Each drive group contains one or more VGs. A VG is responsible for copying data blocks onto alternate media. A VG is capable of managing a single copy of a user file.


See library server.

LS database

The database containing catalog and volume records associated with a library server (LS).


Massive array of idle disks.

managed filesystem

A DMAPI-mounted XFS or CXFS filesystem, configured in a filesystem object in the DMF configuration file, on which DMF can migrate or recall files. (When using the Parallel Data Mover Option, it must be CXFS.)


The maximum number of write child (dmatwc) processes that will be simultaneously scheduled for the VG.


See volume merging.


The integer percentage of active data on a volume less than which DMF will consider a volume to be sparse and allow merging, which should be 0 for a volumegroup that is part of a fast-mount cache.

migrated file

A file that has one or more complete offline copies and no pending or incomplete offline copies.

migrate group

A logical collection of VGs that you combine into a set in order to have a single destination for a migrate request.


The amount of data to be sent to a group member relative to the other members.

offline file

A file whose inode contains a bit-file identifier but whose disk blocks have been removed. The file's data exists elsewhere in copies on alternate media.


A storage library management facility that improves how applications can manage, store, and retrieve removable media.

owner node

The node that DMF will use to perform migrations and recalls on a given shelf. The node on which you run ov_copan becomes the owner node for that shelf. In an HA environment, ownership is transferred as part of HA failover.

parallel data mover node

A node, installed with DMF data mover software and underlying CXFS client-only software, that provides dedicated data mover functionality in addition to the DMF server, increasing data throughput and enhancing resiliency.

Parallel Data Mover Option

Optional software and licenses available for purchase that allow you to run parallel data mover nodes in order to increase data throughput and enhance resiliency.


See configuration parameter.

power budget

The maximum number of RAID sets that can be powered on at any one time.


Redundant array of independent disks.

RAID set

A group of 3 data disks and 1 parity disk on a MAID shelf.

RAID-set identifier

The first four characters of a VSN (which uniquely identifies a specific RAID set within a specific MAID shelf on a specific COPAN cabinet) that can be used as an argument to some OpenVault commands.

resource agent

The software that allows an application to be highly available without modifying the application itself.

shelf identifier

The first three characters of a VSN (which uniquely identifies a specific MAID shelf on a specific COPAN cabinet) that can be used as an argument to some OpenVault commands.


To request that a migrated file's data be moved back onto the filesystem disk, either by explicitly entering the dmget(1) command or by executing another command that will open the file, such as the vi(1) command.

sparse volume

A volume containing only a small amount of active data.


A process initiated by the DMF event mechanism. Configuration tasks that allow certain recurring administrative duties to be automated are defined with configuration file parameters.


See volume group.

volume group

A component of an LS that is responsible for managing a pool of volumes that are capable of storing single copies of user files. Multiple copies of the same user files require the use of multiple VGs. See also LS.

volume merging

The mechanism provided by the LS for copying active data from volumes that contain largely obsolete data to volumes that contain mostly active data. Volume merging is not appropriate for a fast-mount cache.

volume serial number

A label that uniquely identifies a specific volume.


Volume serial number.

write child

A data mover process that migrates data to secondary storage.


A logical grouping of chunks. Zones are separated by file marks and are the smallest block-addressable unit on the tape volume. The target size of a zone is configurable by media type.


The parameter that specifies about how much data the write child should put in a zone.