The AD (Access Duplicate) command duplicates the active access structure or removes a duplicate structure. If you are running cataloging, the name of the active access structure is SYSTEM/CATALOG/<family index>; otherwise, its name is SYSTEM/ACCESS/<family index>.

The system places the duplicate structure on the same family as the original catalog family, but the duplicate structure must be on a different member of the family. The name of the duplicate structure is like that of the original structure except that the family index is different.

By default, the system places the access structure on the halt/load family. You can change this location by using the DL   CATALOG command.

While a duplicate directory is not required to be on the family member that is to receive the duplicate access structure, it is recommended that a duplicate directory be present. Such a practice provides for a reduced probability of losing the access structure. For additional information, refer to  the DD (Directory Duplicate) command.

When you enter the AD command, if it is free of syntax errors, the system starts a visible independent runner named AD. Use the C (Completed Mix Entries) command to find out if the AD command has completed.

Syntax

Explanation

AD (<family index>)

Creates a duplicate access structure on the catalog family member specified by <family index>.

AD − (<family index>)

Removes the duplicate access structure from the specified member of the catalog family.

AD − ON <family name> (<family index>)

Removes a previous and currently unused access structure on the pack specified by <family name> and <family index>.

Examples

Example 1

AD (2)

After you enter the command, the system starts a process called AD. You can check on the progress of the job by entering one of the following monitoring commands:

The following shows a typical display for the A command:

*608 80         :01 Job AD (002)

Example 2

AD - ON DISK (2)

   7268 PK97 SYSTEM/ACCESS/002 REMOVED ON DISK