Dell DR series, Руководство администратора

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NOTE: The DR Series system software includes version checking that limits replication only between other DR
Series systems that run the same system software release version. If versions are incompatible, the administrator
will be notified by an event.
NOTE: It is important to distinguish the difference between data that has been processed by backup, and data that
has been processed by replication. This is because backup saves a copy of data that generally remains
unchanged for a long period of time.
Targets with replication data are read-only, and are updated with new or unique data during scheduled or manual
replications. The DR Series system can be considered to act as a form of a storage replication process in which the
backup and deduplication data is replicated in real-time or via a scheduled window in a network environment. In a
replication relationship between two DR Series systems, this means that a relationship exists between a pair of systems.
One system acts as the source and the other as a target in this replication pair (for example, acme-west and acme-east).
When this type of relationship exists between distinct containers on two distinct DR Series systems, it can be
considered bidirectional in the sense that:
• The West1 container on the acme-west source system can replicate data to a separate East1 container on the
acme-east target system.
• The East2 container on the target acme-east system can also replicate data back to the West2 container on the
source acme-west system.
This form of replication involves separate containers on two distinct DR Series systems. Target containers in replication
must always act as read-only, while sources containers can act as read-write. Unlike NFS and CIFS containers, OST and
RDS container replication is handled by the two supported Data Management Applications (DMAs) on media servers.
For more information on OST, see
Understanding OST . For more information on RDS, see Configuring and Using Rapid
Data Storage .
NOTE: OST and RDS containers are categorized as Rapid Data Access (RDA) containers in DR Series systems.
The DR Series system supports the 64:1 replication of data (32:1 if on DR4X00), whereby up to 64 source DR Series
systems can write data to different individual containers on a single, target DR Series system. This supports the use
case where branch or regional offices can each write their own data to a separate, distinct container on a main
corporate DR Series system.
NOTE: Be aware that the storage capacity of the target DR Series system is directly affected by the number of
source systems writing to its containers, and by the amount being written by each of the source systems.
However, if the source and target systems in a replication pair are in different Active Directory (AD) domains, then the
data that resides on the target system may not be accessible. When AD is used to perform authentication for DR Series
systems, the AD information is saved with the file. This can act to restrict user access to the data based on the type of
AD permissions that are in place.
NOTE: This same authentication information is replicated to the target DR Series system when you have
replication configured. To prevent domain access issues, ensure that both the target and source systems reside in
the same Active Directory domain.
Reverse Replication
The concept of reverse replication is not a supported operation on DR Series systems. This is because replica
containers are always in a R-O (read-only) mode on the DR Series system, thus making write operations a non-
supported operation.
Under very specific conditions, it might be possible for replica containers to support a type of write operation whose
sole function is to restore data from an archival target. For example, data could be replicated back to the remote site
where a data management application (DMA), or backup software, is connected to allow this data to be restored
directly.
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