About the Enterprise Media Manager (EMM) database

The Enterprise Media Manager (EMM) database contains information about media and the robots and drives that are in NetBackup storage units. The NetBackup Resource Broker queries the EMM database to allocate storage units, drives (including drive paths), and media. The host on which the EMM database resides is called the EMM server.

The EMM database contains the following information:

Device attributes
Robotic library and stand-alone drive residence attributes
NDMP attributes
Barcode rule attributes
Volume pool attributes
Tape attributes
Media attributes
Storage unit attributes
Storage unit group attributes
Hosts with assigned tape drives
Media and device errors
Disk pool and disk volume attributes
Storage server attributes
Logon credentials for storage servers, disk arrays, and NDMP hosts
Fibre Transport attributes

The EMM database ensures consistency between drives, robotic libraries, storage units, media, and volume pools across multiple servers. The EMM database contains information for all media servers that share devices in a multiple server configuration.

The NetBackup scheduling components use the EMM database information to select the server, drive path, and media for jobs. When the device manager ltid starts up, it reads device information from the EMM database into a shared memory segment. Components on the same host communicate by using shared memory IPC or socket protocols. Socket protocols are used between components across multiple hosts. Command line interfaces are available to obtain run-time (shared memory) information and static device configuration information.