Determine DFSR staging quota

Note: This article applies to Windows Server 2008 and later versions.

Distributed File System Replication (DFSR) is used to replicate data from DFS namespaces across a group of servers that are called
a replication group. This allows data to stay synchronized on multiple servers. This artivle helps you to determine the staging
quota size.

Rule of thumb

Windows Server 2008 and 2008 R2: The staging area quota must be as large as the 32 largest files in the replicated folder.

How to find the largest files

Perform the following steps in PowerShell®:

1. Run the following to get the names and sizes of the largest 32 files in bytes:

   $ Get-ChildItem c:\temp -recurse | Sort-Object length -descending | select-object -first 32 | ft name,length -wrap -auto
   

2. Run the following to get the total size of the 32 largest files:

   $ Get-ChildItem c:\temp -recurse | Sort-Object length -descending | select-object -first 32 | measure-object -property length –sum
   

3. Run the following to provide the total size of the 32 largest files in gigabytes:

   $ $big32 = Get-ChildItem c:\temp -recurse | Sort-Object length -descending | select-object -first32 | measure-object -property length –sum
   $big32.sum /1gb

Calculate the minimum size required

From the output of one of the commands above, you get the following information:

• Name: file name
• Length: size in bytes
• One gigabyte: 1073741824 bytes

Sample output

Here is an example of the output using the 16 largest files:

	Name         | Length
	------------ | -------------
	File1.zip | 10286089216
	File2.zip | 6029853696
	File3.zip | 5751522304
	File4.zip | 5472683008
	File5.zip | 5241586688
	File6.zip | 4321264640
	File7.zip | 4176765952
	File8.zip | 4176765952
	File9.zip | 4078994432
	File10.zip | 4058424320
	File11.zip | 3858056192
	File12.zip | 3815138304
	File13.zip | 3815138304
	File14.zip | 3576931328
	File15.zip | 3307488256
	File16.zip | 3274982400

Calculations

To get the minimum staging area quota using the first two powershell commands, you would take the sum of the total number of bytes
and divide it by one gigabyte. In the preceding example, we used 16 files instead of 32. You would take the sum, which is
75241684992, and divide it by 1073741824.

75241684992 / 1073741824 = 70.07 GB

The third powershell command is the easiest because it does the math for you.

$ PS C:\> $big32 = Get-ChildItem c:\temp -recurse | Sort-Object length -descending | select-object -first32 | measure-object -property length -sum<br>
$ PS C:\>$big32.sum /1gb<br>
70.07427978515625

In this case, you would set the staging quota to 71 GB.

You don't need to reboot after you set the quota, but you do need to wait for the Active Directory (AD) and DFSR AD polling cycle
for the changes to apply.