How NetBackup creates the path to DFSR data

Problem

For DFSR backups, the Replicated Folder is the basic unit of backup in much the same way as a drive or directory would be for a non-DFSR backup.

The NetBackup path starts with a standard location common to all DFSR Replicated Folders
Example:
Shadow Copy Components:\User Data\Distributed File System Replication\DfsrReplicatedFolders

When specifying a more granular file set, NetBackup then appends the DFSR Replicated Folder name to the path
Example:
Shadow Copy Components:\User Data\Distributed File System Replication\DfsrReplicatedFolders\Docs

When duplicated Replication Folder names appear NetBackup must uniquely identify each folder by appending the GUID for the Replication Group to the Replicated Folder name
Example:
Shadow Copy Components:\User Data\Distributed File System Replication\DfsrReplicatedFolders\Docs (B203D995-F689-4692-9852-B7B6CA95ACC2-25665971-2969-4FD4-9537-ECE5782331A9)

Cause

When NetBackup interrogates Shadow Copy Components, the 'DFS Replication service writer' provides NetBackup with the Replicated Folder names for each Replication Group.  A Replicated Folder name can be identical between Replication Groups.

NOTE: There can't be two identical Replicated Folder names in the same Replication Group).

DFS Management Console Example 1:

When using the DFS Management console to create either a new Replication Group or to add a new Replicated Folder to an existing Replication Group, the default Replicated Folder name is based on the path.  Although this can be customized, this default makes the Replicated Folder name likely to be the name of the replicated folder itself.

DFS Management Console Example 2:
  

As noted above, NetBackup starts with a path common to all DFSR environments, then adds on the Replicated Folder name.

Example:
Shadow Copy Components:\User Data\Distributed File System Replication\DfsrReplicatedFolders\Docs

For duplicate Replicated Folder names, NetBackup generates a unique path by adding the GUID for the Replication Group to the Replicated Folder name.

Example as observed in Backup Archive and Restore:

 

'diskshadow' output showing the GUID assigned to a Replication Group:

+ Component "DFS Replication service writer:\DfsrReplicatedFolders\B203D995-F689-4692-9852-B7B6CA95ACC2-25665971-2969-4FD4-9537-ECE5782331A9"
     - Name: B203D995-F689-4692-9852-B7B6CA95ACC2-25665971-2969-4FD4-9537-ECE5782331A9
     - Logical path: DfsrReplicatedFolders
     - Full path: \DfsrReplicatedFolders\B203D995-F689-4692-9852-B7B6CA95ACC2-25665971-2969-4FD4-9537-ECE5782331A9
     - Caption: Docs
     - Type: VSS_CT_FILEGROUP [2]
     - Is selectable: TRUE
     - Is top level: TRUE
     - Notify on backup complete: TRUE
     - Components:
     - File List: Path = Y:\Departments\English\Docs, Filespec = *
     - Paths affected by this component:
          - Y:\Departments\English\Docs

NOTE: For more information on the 'diskshadow' command, see TECH76997 linked below.

Solution

Problem avoidance is the best solution

NOTE ON DFSR ADMINISTRATION: Veritas highly recommends building your DFSR environment so that a Replicated Folder name is not repeated among multiple Replication Groups. Although NetBackup can backup data using the unique name generated by the Replicated Folder name plus the GUID, doing this creates at least two problems.

Problem 1:
Confusion.  Determining which "Docs" folder (using the above example) is which, requires unlikely knowledge of DFSR and NetBackup. (see the NOTE ON IDENTIFICATION below)

Problem 2:
The names are not stable.  Consider what happens when there is only one "Docs" folder and a second "Docs" is added.  One will get the GUID name and the other does not.  This has the potential to change any existing backups in that they can no longer be restored (to the original location) since the name has changed.  The same issue would occur if there were a collection of "Docs" and some were deleted or renamed.

Working within the issue:
When backing up ALL_LOCAL_DRIVES or when backing up all of DFSR using the standard common DFSR path, the above information is less relevant.

However, it is often necessary to break up large amounts of DFSR content into separate backup streams to reduce the per-stream size.

When Replicated Folder names are not unique, it is not practical to type the large path produced with the addition of the GUID in the path name into a Policies Backup Selections.

You can follow these steps to make this processes easier:

On the DFSR Client
1. Launch Backup Archive and Restore
2. Click "Select for Backup" and drill into: Shadow Copy Components:\User Data\Distributed File System Replication\DfsrReplicatedFolders
3. For each desired path, rt-click the path and select "Add to Exclude list" (you will remove these entries from the Exclude list in step 7 below)

4. Launch regedit and navigate into: HKLM\Software\Veritas\NetBackup\CurrentVersion\Config
5. Open the key named Exclude and observe in addition to the 5 default exclude rows, all paths excluded in step 3 above, are present
6. Copy the DFSR paths from this list and add them to the DFSR Policies 'Backup Selections' as needed
7. Delete the DFSR paths from the Exclude registry key (or else the DFSR content in these paths will not get backed up)

NOTE ON RESTORES:  When restoring DFSR content which has appended the 73 character GUID, if restoring to the Original Location, the data will get restored into its original path without tagging on the 73 digit GUID.  However, when restoring to an alternate path, it will restore with the 73 digit GUID as part of the folder name.

NOTE ON IDENTIFICATION: One way to understand which Replication Folder name belongs to which logical path and which GUID, is the following:

1. Use Internet Explorer, to open the file: ...\NetBackup\logs\beds\{2707761B-2324-473D-88EB-EB007A359533} - DFS Replication service writer.xml
2. This file contains a section called "FILE_GROUP" for each Replicated Folder. Within each FILE_GROUP section the following items are listed:

     A. componentName = which is the unique GUID for the Replicated Folder
     Example: componentName="B203D995-F689-4692-9852-B7B6CA95ACC2-25665971-2969-4FD4-9537-ECE5782331A9"

     B. caption = which is the Replicated Folder name
     Example: caption="Docs"

     C. FILE_LIST = which is the logical path to the replicated folder itself
     Example: FILE_LIST path="Y:\Departments\English\Docs"