the installation fails. To upgrade a NetBackup media server that hosts a PDDO
agent, you must first remove the PDDO agent.
See the NetBackup PureDisk Deduplication Option (PDDO) Guide.
Deduplication within each media server deduplication node is supported; global
deduplication between nodes is not supported.
About NetBackup Client Deduplication
With normal deduplication, the client sends the full backup data stream to the
mediaserver. Thededuplication engine onthe mediaserver processesthe stream,
saving only the unique segments.
With NetBackup Client Deduplication, the client hosts the PureDisk plug-in that
duplicates the backup data. The NetBackup client software creates the image of
backed up files as for a normal backup. Next, the PureDisk plug-in breaks the
backup image into segments and compares them to all of the segments that are
storedinthat deduplicationnode.The plug-inthensends onlythe uniquesegments
to the NetBackup Deduplication Engine on the storage server. The engine writes
the data to a media server deduplication pool.
Client deduplication does the following:
■ Reduces network traffic. The client sends only unique file segments to the
storage server. Duplicate data is not sent over the network.
■ Distributes some deduplication processing load from the storage server to
clients. (NetBackup does not balance load between clients; each client
deduplicates its own data.)
Figure2-2 showsclient deduplication. Thededuplication storageserver is amedia
server on which the deduplication core components are enabled.
Planning your deployment
About NetBackup Client Deduplication
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