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DFS and/or Robocopy

EMJTech asked
Medium Priority
Last Modified: 2010-05-18
Here's a brief description of my network:

4 physical sites, each with a T1 connection to the main headquarters.  Local DC's running Win2K3 in each site and wanting to use DFS to replicate about 200GBs worth of data in real time.  I know Microsoft recommends DFS for use with less than 64GB worth of data, but once the data is on each DC, I don't think the volume of changes will be extreme.  Is there a way to pre-stage the DFS share with Robocopy or will this just screw up my DFS replication?

Any alternatives will be appreciated.  I would like to use the DFS namespace to centralize my shares and limit mapped drive changes, but am not sure that DFS (or NTFRS) can handle the amount of data initially...
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Yes...you can prestage data for DFS replication:  Windows 2003 R2 way of doing it:  http://technet2.microsoft.com/WindowsServer/en/Library/d3afe6ee-3083-4950-a093-8ab748651b761033.mspx

Simple and flexible prestaging of new servers
Before adding a new server to a replication group, administrators can prestage the replicated folders on the target servers by copying the data to the servers, restoring a backup, or copying files from a tape, DVD, or removable hard disk. As described earlier, the synchronization process is very efficient in terms of bandwidth usage and metadata exchanged, resulting in minimal WAN traffic during the initial synchronization for files that are the same on the source server (known as the primary member) and target servers. If the files on the target server are out-of-date, DFS Replication will use RDC to replicate only the changes that occurred since the data was prestaged. Any prestaged files that existed on the target servers, but not on the source server, are moved to the PreExisting folder under the target server's replicated folder path.

Windows 2003:

There is a way to prestage content in FRS, but it can only be done on a
third member, not the initial two. The prestaging process involves enabling
replication between two initial members, waiting for data to be sync'd,
making a backup of the replicated files, restoring the files on the third
member, and enabling FRS (this is simplified--it's actually more
complicated). And yes, data is temporarily moved into the pre-existing
folder on the third member but is moved back to the replica tree when FRS
confirms the files are identical.

The process is described here:

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by the way, I would upgrade your DFS servers to Windows 2003 R2.  DFS replication is greatly been enhanced in Windows 2003 R2.


That's what I had thought...

Question.... is Microsoft now supporting more than 64GB worth of replicated data with R2?  I thought I saw that on the link you gave, but wanted to be sure I was reading it correctly.

So, to clarify, if I use Robocopy to copy all of my data from server A to Server B (or copy all data to a usb drive and then copy back to server B) and then enable DFS replication, will it throw all the files I just copied into the PreExisting folder or will it just double-check that the files are identical and keep on chugging?

Right now, I only have 2 servers to replicate, so I don't have a 3rd to pre-stage as has been suggested to me elsewhere.  Additionally, I have 2 more DC's that I would like to enable DFS replication on for this same data at a later time, but with R2 am I going to be killing my WAN?
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