About MSDP compression
NetBackup deduplication hosts provide compression for the deduplicated data. It is separate from and different than NetBackup policy-based compression.
Compression is configured by default on all MSDP hosts. Therefore, backups, duplication traffic, and replication traffic are compressed on all MSDP hosts. The data also is compressed on storage.
Table: MSDP compression options describes the compression options.
A different topic describes the interaction of the encryption and the compression settings for MSDP.
Table: MSDP compression options
Option | Description |
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Compression for backups
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For backups, the deduplication plug-in compresses the data after it is deduplicated. The data remains compressed during transfer from the plug-in to the NetBackup Deduplication Engine on the storage server. The Deduplication Engine writes the encrypted data to the storage. For restore jobs, the process functions in the reverse direction.
The COMPRESSION parameter in the pd.conf file on each MSDP host controls compression and decompression for that host. By default, backup compression is enabled on all MSDP hosts. Therefore, compression and decompression occur on the following hosts as necessary:
The clients that deduplicate their own data (that is, client-side deduplication). The load balancing servers. The storage server.
MSDP compression cannot occur on normal NetBackup clients (that is, the clients that do not deduplicate their own data).
Do not enable backup compression by selecting the option on the Attributes tab of the Policy dialog box. If you do, NetBackup compresses the data before it reaches the plug-in that deduplicates it. Consequently, deduplication rates are very low. Also, NetBackup does not use the Deduplication Multi-Threaded Agent if policy-based encryption is configured.
See About the MSDP Deduplication Multi-Threaded Agent.
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Compression for duplication and replication
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For duplication and replication, the deduplication plug-in compresses the data for transfer. The data remains compressed during transfer from the plug-in to the NetBackup Deduplication Engine on the storage server and remains compressed on the storage.
The OPTDUP_COMPRESSION parameter in the pd.conf file controls compression for duplication and replication. By default, duplication and replication compression is enabled on all MSDP hosts. Therefore, duplication and replication compression occurs on the following MSDP servers:
Duplication and replication compression does not apply to clients.
NetBackup chooses the least busy host to initiate and manage each duplication job and replication job. To ensure that compression occurs for all optimized duplication and replication jobs: do not change the default setting of the OPTDUP_COMPRESSION parameter.
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