The following list describes the backup process when a media server deduplicates the backups and the destination is a Media Server Deduplication Pool:

• The NetBackup Job Manager (nbjm) starts the Backup/Restore Manager (bpbrm) on a media server.

• The Backup/Restore Manager starts the bptm process on the media server and the bpbkar process on the client.

• The Backup/Archive Manager (bpbkar) on the client generates the backup images and moves them to the media server bptm process.

  The Backup/Archive Manager also sends the information about files within the image to the Backup/Restore Manager (bpbrm). The Backup/Restore Manager sends the file information to the bpdbm process on the primary server for the NetBackup database.

• The bptm process moves the data to the deduplication plug-in.

• The deduplication plug-in retrieves a list of IDs of the container files from the NetBackup Deduplication Engine. Those container files contain the fingerprints from the last full backup for the client. The list is used as a cache so the plug-in does not have to request each fingerprint from the engine.

• The deduplication plug-in separates the files in the backup image into segments.

• The deduplication plug-in buffers the segments and then sends batches of them to the Deduplication Multi-Threaded Agent. Multiple threads and shared memory are used for the data transfer.

• The NetBackup Deduplication Multi-Threaded Agent processes the data segments in parallel using multiple threads to improve throughput performance. The agent then sends only the unique data segments to the NetBackup Deduplication Engine.

  If the host is a load-balancing server, the Deduplication Engine is on a different host, the storage server.

• The NetBackup Deduplication Engine writes the data to the Media Server Deduplication Pool.

  The first backup may have a 0% deduplication rate, although a 0% rate is unlikely. Zero percent means that all file segments in the backup data are unique.