Remote Replication - Quantum DXi4500 User Manual

Remote Replication

Quantum DXi4500 User's Guide
deduplication engine searches for new data entering the DXi and uses a
"variable length compression type algorithm" to compare this to
existing data in the block pool. Unique blocks are added to the block
pool and known blocks are indexed.
The space reclamation function searches the blockpool for data blocks
that are not referenced by any pointers (that is, the files associated with
the block have been expired and removed). Once such a data block is
identified, the index count is decremented, and the block is removed to
make the space reusable.
Note that the space reclamation process can use a significant amount of
CPU processing and disk I/O. Therefore it is important to know when to
schedule the space reclamation process. By default the process will
commence every Sunday at 12:00pm. However, to maximize
performance and capacity utilization, it is highly recommended that this
process is performed on a daily basis. As best practice it is
recommended that this process commences at least two hours 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.
Today most backup occurs on isolated devices, making it difficult to
deploy disk backup when disaster recovery protection is required. DXi-
Series solutions use data deduplication and replication to decrease by
up to 100 times 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 DXi-Series replication, users can transmit data from a single site or
multiple sites to a central location using any DXi model. DXi-Series
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, replication, and
tape for an optimal combination of performance, simplicity, and
security.
Chapter 1: DXi4500 System Description
Remote Replication
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