Set up item libraries

Use item libraries in the Administration Console to specify the operating system folder for storing the associated item files, and the required level of protection for that folder.

In this topic:

Guidelines for managing item libraries

In the Object Types section of the Administration Console, you can manage item libraries:

• Define the default item library to use for all item types in the product.

• Define the item library for a specific item type to override the default library for the product.

• Remove the item library for a specific item type.

• Remove the default item library for the product.

To work with item libraries, you need the Manage Libraries privilege.

Guidelines for maintaining the integrity of the library data:

• Do not use the directories that store libraries for any non-Dimensions CM files or subdirectories.

• Use each library for items of one or more types that belong to a single product.

• Make sure that there is adequate disk space available. Any disk-space quota limits, if enforced, must be sufficient.

• Keep library names well within any operating system limits, such as the total file name length and number of subfolder levels. In general, keep folder names to 50-60% of any operating system limits.

• Make sure that you do not use the same folder name for libraries in multiple databases. This would cause Dimensions CM to be unaware of potential clashes with file names when operating on any of these databases.

As a Product Manager, you can change item libraries. But Dimensions CM does not move the library contents to correspond with the changes, and only issues a warning advising you to move the files.

After making changes to item libraries in the Administration Console, manually transfer the files in the library directories to a new location. Only then you may allow other users to access the libraries for the product.

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About item libraries

An item library is an operating system folder for storing the associated item files, including the required level of protection.

You can assign a default item library for all the items in a product, and define an item library that overrides the default for a specific item type. The latter is recommended for an item type where you anticipate a substantial number of items of that type.

Item libraries can be stored on remote servers accessed using UNC path names, or using mapped drives. These could be a Windows Network Access Storage (NAS), a fiber connected storage area network (SAN), or a network share on a PC.

When you define item libraries, Dimensions CM creates any directories and subdirectories that do not yet exist.

Generally, items that are machine-readable entities, such as software or documentation, are stored directly in the item libraries under the Dimensions CM control. When an item is not a machine-readable entity (for example, hardware that has design parts represented by part numbers), then a documentary control record must be created and maintained. This is a placeholder item file that represents and documents the existence of the physical item.

When defining an item library, you need to specify the following:

• The host machine. See Define the host node.

• The folder path. See Set the folder path.

• Protection. See Set up protection.

• Whether to use delta storage. See Use delta storage.

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Define the host node

You can define item libraries to enable users with appropriate permissions to access the items stored in these libraries from any network node.

A network can consist of nodes running on different operating systems and networked in a variety of ways using TCP/IP. For details about networking aspects, see Administration.

If the Dimensions Network is installed and running, the host IDs (up to 20 characters and case-sensitive) define the node on the network where the item libraries are located. The Tool Manager predefines these host IDs when setting up and maintaining the network.

You must select a node for the item library. An asterisk (*) is not a valid entry. If you enter a node that is not known to the Dimensions Network, you receive an error message when creating the library.

If the Dimensions Network is not installed, all file names must be on the local node. To ensure this, enter the node name of the Dimensions CM server in the combo box.

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Set the folder path

The folder path specifies the area on the host machine where one or more item libraries are stored.

You may store multiple item types in the same library by specifying the same folder path, as long as all the item types use the same library storage scheme (Normal or Delta).

Depending on the system, define the folder path as follows:

Windows	The folder path is an absolute path ending with a backslash (\). For example: c:\usr\user1\libraries\type_src\
UNIX	The folder path is an absolute path ending with a forward slash (/). For example: /usr/user1/libraries/type_src/
z/OS	For details, see Dimensions for z/OS.

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Set up protection

Using the Protection option, you can change the default protections assigned to an item library during creation.

Depending on the system, the protection defined as follows:

Platform	Description
UNIX	For libraries on UNIX, the Protection field specifies what access to the Dimensions CM libraries is permitted directly using the operating system. The normal access indicators are: R = read, W = write, X = execute Use these indicators in appropriate combinations to provide the level of protection. The format in which the protection is defined to Dimensions CM is: <owner>, <group>, <world> For example: RX,RX, In this example, <world> has no access indicators and, therefore, no access to the folder, except access to Dimensions CM items using Dimensions CM control.
Windows	For libraries on Windows, the Protection field is left empty during library creation. After creating a library folder and before using it, you specify the protection level required for operating-system access by creating an ACL (Access Control List) for it.
z/OS	For libraries on z/OS systems, protection is not provided.

For libraries on all relevant operating systems, the criteria for choosing a protection level is that the protection level specifies what access is required other than using Dimensions CM. For example, RX,, may be sufficient on UNIX.

Dimensions CM always grants users access to an item, provided that the users hold the required role.

Exception: With a folder item, although the archive/save-set file that comprises a foldr item may itself be retrieved as described, its reconstruction into directories is dependent on the user having access permissions compatible with those recorded for the directories and files in the archive/save-set.

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Use delta storage

On UNIX and Windows, you can store items using the native Version Manager delta library storage scheme.

In the delta library storage scheme, different revisions of the same item are stored as deltas of previous revisions. This ensures better use of disk space, especially for text files.

Delta libraries are not recommended for binary item files such as executables. Some factors may cause delta libraries to be less efficient, such as long record lengths, the speed of the delta processing and lastly, internal limits on the number of file branches.

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See also:

• Add item libraries
• General details of object types