Explanation of Distributed, Centralized and Replicated Catalog Modes in Backup Exec for Windows Server.

Problem

Explanation of Distributed, Centralized and Replicated Catalog Modes in Backup Exec for Windows Server.

Solution

There are three modes of Catalog Storage :
 
1.Distributed
2.Centralized
3.Replicated
 
Centralized catalog and restore operations for the Managed Media Server (MMS) from both the Managed Media Server and the Central Administration Server (CAS) is possible because of these modes of catalog storage. 
 
Distributed Catalog Mode
 
Image files, which are small files that contain information about the backup set, are distributed to the CAS from every MMS. History files, which contain detailed information about the backup set, remain on the MMS.
 
Note: It is important that the catalog files on the managed media server are backed up since most catalog information is kept here when the distributed catalog location is used.
 
When the catalog is distributed, the view of the restore selections on the CAS displays only the backup set at the volume level. Backup set details are not displayed if the MMS that created this backup set is not available, but the whole volume can be restored from the CAS.
 
A distributed catalog provides increased performance, default centralized restore capability, and decreased network traffic. If a MMS does not have a persistent connection to the CAS, then whenever the MMS does connect, the image files in the catalog are automatically distributed to the CAS. The temporary increase in network traffic caused by the catalog distribution is not significant.
 
Centralized Catalog Mode
 
All catalog files and information for the MMS are kept on the CAS. 
 
Replicated Catalog Mode
 
All catalog files are replicated from the MMS to the CAS. Both the MMS and the CAS store the catalog produced by the MMS. Deletions of catalog files are replicated between the MMS and the CAS only when the catalog files are deleted by Backup Exec according to the catalog settings. If catalog files on the MMS are deleted as a result of an archive operation or a manual deletion, the deletions are replicated the next time that the catalogs are synchronized.
 

Regardless of the catalog location, if a persistent network connection is available between the CAS and the MMS, then you can browse the backup sets in the catalog and perform restore operations from both servers.

The below registry value stores the catalog mode :
 
HKEY_LOCAL_MACHINE\SOFTWARE\SYMANTEC\Backup Exec For Windows\Backup Exec\Catalogs -> Catalog Mode

DISTRIBUTED = 0
CENTRALIZED = 1
REPLICATED = 2