Dell PowerVault DP600 - Manual (Page 54)

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easier, but, depending on the size of the protected data and the speed of the network, manual
replica creation can be faster.
To help you choose a replica creation method, the followingtable provides estimates for how long
DPM takes to create a replica automatically over the network given different protected data sizes
and network speeds. The estimates assume that the network is running at full speed and that
other workloads are not competing for bandwidth. Times are shown in hours.
Hours to Complete Automatic Replica Creation at Different Network Speeds
Size of Protected
Data
512 Kbps 2 Mbps 8 Mbps 32 Mbps 100 Mbps
1 GB 6 1.5 < 1 < 1 < 1
50 GB 284 71 18 5 1.5
200 GB 1137 284 71 18 6
500 GB 2844 711 178 45 15
Important
If you are deploying DPM to protect data over a WAN and your protection group includes
more than 5 GB of data, we recommend that you choose the manual method for creating
the replicas.
Automatic Replica Creation
For large replica creation jobs, you might want to schedule the job to run only during periods of
light network traffic.
Manual Replica Creation
If you choose manual replica creation, DPM specifies the precise locations on the DPM server
where you must create the replicas. Typically, you create the replicas by restoring your most
recent backup of the data source from removable media such as tape. After you restore the data,
you complete the process by running synchronization with consistency check for each of the
replicas.
It is crucial that when you restore the data to the DPM server to create the replica, you retain the
original directory structure and properties of the data source, such as time stamps and security
permissions. The more discrepancies that exist between the replicas and the protected data
source, the longer the consistency checking part of the process takes. If you do not preserve the
original directory structure and properties, manual replica creation can take as long as automatic
replica creation.