Microsoft Dfs file protection methods

There are some methods that you can use to protect the data in your Microsoft Dfs environment.

About this task

Here are the methods you should use to protect your Microsoft Dfs data:

Procedure

Back up the Dfs link metadata and the actual data at the share target of each link from the workstation hosting the Dfs root. This method simplifies back up and restore by consolidating all of the Tivoli® Storage Manager activities on a single workstation. This method has the disadvantage of requiring an additional network transfer during backup to access the data stored at link targets.
Back up only the Dfs link metadata that is local to the workstation hosting the Dfs root. Back up the data at the target of each link from the workstation(s) which the data is local too. This method increases back up and restore performance by eliminating the extra network transfer, but requires Tivoli Storage Manager back up and restores to be coordinated among several workstations.

Results

Note:

See the product README file for current limitations of this feature.

Files contained on a Dfs server component are accessed using a standard UNC name, for example:

\\servername\dfsroot\

where servername is the name of the host computer and dfsroot is the name of the Dfs root.

If you set the dfsbackupmntpnt option to yes (the default), an incremental backup of a Dfs root does not traverse the Dfs junctions. Only the junction metadata is backed up. This is the setting you should use so that Tivoli Storage Manager can be used to restore Dfs links.

You can use the dfsbackupmntpnt option to specify whether Tivoli Storage Manager sees a Dfs mount point as a Microsoft Dfs junction or as a directory.

Important: Restore the Dfs junction metadata first. This recreates the links. Then restore each junction and the data at each junction separately. If you do not restore the junction metadata first, Tivoli Storage Manager creates a directory under the Dfs root using the same name as the junction point and restores the data in that directory.

The following example relates to method 1 above and illustrates how to use Tivoli Storage Manager to back up and restore a Microsoft Dfs environment. Assume the existence of a domain Dfs environment hosted by the workstation almaden:

Dfs root: \\almaden\snj64test
Dfs link1: \\almaden\snj64test\tools
Dfs link2: \\almaden\snj64test\trees

Backup procedure:

Set the dfsbackupmntpnt option to yes in your client options file (dsm.opt).
Enter the following command to back up link junction information:
```
 
dsmc inc \\almaden\snj64test
```
Enter the following command to back up data at the tools link:
```
 
dsmc inc \\almaden\snj64test\tools
```
Enter the following command to back up data at the trees link:
```
 
dsmc inc \\almaden\snj64test\trees
```

Note: DFS Replication uses staging folders to act as caches for new and changed files to be replicated from sending members to receiving members. If you do not want to backup these files, you can exclude them from your backup using the exclude.dir option.

exclude.dir x:\...\Dfsrprivate

Restore procedure:

Manually recreate shares at target workstations only if they no longer exist.
Manually recreate the Dfs root using the exact name as it existed at the time of back up.
Enter the following command to recover data from the tools link. This step is not necessary if the data still exists at the link target:
```
  dsmc restore \\almaden\snj64test\tools\* -sub=yes
```
Enter the following command to recover data from the trees link. This step is not necessary if the data still exists at the link target:
```
  dsmc restore \\almaden\snj64test\trees\* -sub=yes
```
Use the Distributed File System management console snap-in to reestablish replication for each link, if necessary.

Tivoli Storage Manager limitations:

Tivoli Storage Manager does not restore root of Dfs. To recreate the Dfs tree, manually create the Dfs root first, then start restore to recreate the links.
Tivoli Storage Manager can back up the Dfs tree (both domain based Dfs and stand alone Dfs) hosted on local workstation only. You cannot back up Dfs if the Dfs host server is not your local workstation.
Tivoli Storage Manager cannot recreate shared folders on restore. For example, if you delete the junction and the shared folder the junction points to, restoring the Dfs root recreates the Dfs junction, but restoring a junction creates a local folder instead of creating the original backed up shared network folder.
If a Dfs link is created with replica and the replica share is on a different server, then Tivoli Storage Manager does not display the replica data.
If a Dfs root is added or modified, Tivoli Storage Manager will not back it up. You must specify the Dfs root in the domain option in the client options file (dsm.opt) regardless of whether DOMAIN ALL-LOCAL is specified.