Dell PowerVault DR2000v - Manual (Page 17)

Series systems, the AD information is saved with the file. This can serve 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 supported 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), also known as backup software, is connected to allow
this data to be restored directly.
This specific case applies only to configurations where data is backed up from a remote location to a local container,
and then replicated over a WAN to a replica container that is backed up to tape backup. The data needs to be restored
from the tape backup to the original location; first, restore the data back to a DR Series system replica container, and
then restore it back to the original source location of the data on the other side of the WAN link.
NOTE: If you choose to use this alternate workaround method, you must set up a new data storage unit in the DMA
and import the images before a restore to the original location can occur.
To support this effort to leverage deduplication across the WAN to allow this scenario, complete the following:
1. Make sure that the replication operation has completed (between source and target).
2. Delete current replication relationship, and re-create replication relationship (reversing the source and target
roles).
3. Restore data to the original source container (now the target).
4. Make sure that the replication operation has completed.
5. Delete replication relationship and re-create replication relationship (restoring original source and target
destinations).
Under this scenario, a fraction of the data to be recovered is sent across the WAN link. This could speed up a remote
restore significantly. However, there are some downsides to this type of scenario:
• If step 1 is not followed correctly, any changes not fully replicated are lost.
• During steps 2 and 3, any data that is written to the original DR Series system source container may be lost.
• During step 4, if the data is not fully replicated back before the switch is made, it may be lost.
Alternatively, you still could support this effort by completing the following:
1. Create a new container on the target DR Series system.
2. Set up replication from this container back to the source DR Series system container.
3. Set up a new disk storage unit in the DMA and make sure that the DMA is aware of any new images.
4. Import the old images back into the DMA from the target DR Series system (the original source location).
5. Use a new disk storage unit in the DMA, and then restore the data back to the original client.
Data Deduplication and Compression
The DR Series system design uses various data-reduction technologies, including advanced deduplication algorithms, in
addition to the generic and custom compression solutions that prove effective across many differing file types. Data
deduplication and compression is addressed in the following areas:
• DR Series System — The DR Series system backup and recovery appliances provide both efficient and high-
performance disk-based data protection to leverage the advanced deduplication and compression capabilities in the
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