System Description
Space Reclamation
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Space Reclamation
The space reclamation process performs multiple functions on the ETERNUS CS800.
When data is deduplicated it is stored in a blockpool — a pool of all unique data blocks that
were captured during the data deduplication cycle. When subsequent backup jobs occur,
the data deduplication engine searches for new data entering the ETERNUS CS800 and
uses a variable length compression algorithm to compare new data to existing data in the
blockpool. Unique blocks are added to the blockpool and known blocks are indexed.
The space reclamation function searches the blockpool for data blocks that are not refer-
enced by any pointers (that is, the files associated with the block have been expired and
removed). Once such a data block is identified, the block is removed to make the space
reusable.
It may be beneficial to schedule space reclamation for a time when other operations are not
normally being carried out. Therefore it is important to know when to schedule the space
reclamation process. By default the process will commence daily at 01:00 pm. As best
practice it is recommended that this process commences after your backup job has
completed on a daily basis. It is far more efficient to process a day’s worth of new data than
a week’s worth.
Remote Replication
Today most backup occurs on isolated devices, making it difficult to deploy disk backup
when disaster recovery protection is required. The ETERNUS CS800 solution uses data
deduplication and replication to decrease the bandwidth required to move backup data over
networks and between sites. This dramatic gain makes it practical and cost-effective for
users to replicate backup data over WANs for secure, network-based disaster recovery
protection, and it lets users combine rapid, local restores with sound disaster recovery
protection.
With ETERNUS CS800 replication, users can transmit data from a single site or multiple
sites to a central location using any ETERNUS CS800. The replication is an asynchronous,
automated background process that includes encryption of data in transit. This model for
protecting the distributed enterprise allows users to combine disk storage, remote repli-
cation and tape backup for an optimal combination of performance, simplicity and security.
For more information on implementing a replication plan, see Chapter
Summary of Contents for ETERNUS CS800 S5
Page 1: ...Edition June 2014 English ETERNUS CS800 S5 V2 3 1 User Guide ...
Page 14: ...Contents U41840 J Z125 7 76 ...
Page 30: ...Environmental Protection Important Information 28 U41840 J Z125 7 76 ...
Page 48: ...Network Configuration System Description 46 U41840 J Z125 7 76 ...
Page 80: ...Locating the Serial Number Hardware Description and Basic Operations 78 U41840 J Z125 7 76 ...
Page 116: ...Further Configurations Installing the ETERNUS CS800 S5 Modules 102 U41840 J Z125 7 76 ...
Page 150: ...The Remote Management Console Remote Management 136 U41840 J Z125 7 76 ...
Page 190: ...AIS Connect Configuration Wizards 176 U41840 J Z125 7 76 ...
Page 200: ...Current Activity Overview Home Page 186 U41840 J Z125 7 76 ...
Page 301: ...Configuration System U41840 J Z125 7 76 287 Figure 177 Network Configuration ...
Page 353: ...Configuration Contacts U41840 J Z125 7 76 339 Figure 211 Primary and Secondary Pages ...
Page 402: ...Reports Replication 388 U41840 J Z125 7 76 ...
Page 406: ...Hardware Status 392 U41840 J Z125 7 76 Figure 236 System Board Page ...
Page 432: ...Activity Log Status 418 U41840 J Z125 7 76 ...
Page 442: ...Service Tickets Alerts 428 U41840 J Z125 7 76 ...
Page 462: ...Reboot Shutdown Utilities 448 U41840 J Z125 7 76 ...
Page 470: ...Common Problems and Solutions Troubleshooting 456 U41840 J Z125 7 76 ...
Page 496: ...Additional Specifications for Scale Mode System Specifications S5 626 U41840 J Z125 7 76 ...
Page 634: ...Index 634 U41840 J Z125 7 76 ...