The AR (Archive Release) command supports the catalog subsystem, not the archive (backup and restore) subsystem. It starts the MCP independent runner called ARCHIVEHANDLER, which releases an old archive log and creates a new one. The system stores the archive log on the CATALOG family. When the archive log is full (it holds about 60,000 records), the operating system automatically releases it. When it is released, an archive log is crunched and marked as a nonsystem file.
To use this command, the cataloging and archiving options must be set. Refer to “CATALOGING (Option 23)” and “ARCHIVING (Option 28)” in the OP (Options) command.
Syntax

Explanation
AR
If no file title is specified, the online archive log is released and a new one created.
AR <file title>
If a file title is specified and that file is an archive log, the file is released so that it can be removed. (Archive logs are system files.) This feature is useful when a change of the halt/load family causes an archive log to remain on disk as a nonremovable system file.
Example
AR
MSG
--Mix--Time------------------- MESSAGES -------------------- *4080 16:26 A NEW ARCHIVELOG HAS BEEN CREATED 4080 16:25 THE ARCHIVELOG WAS RELEASED