DFS File Replication

[nervous2]

I have two separate Domains in two remote locations linked with a VPN with a trust set between the two, both computers can see each domain and everything in that respect seems to be working fine.

Location A is where my main files and documents are served and Location B needs to access them as well in relatively real time make changes as well. I decided to set up DFS so that Location B could get fast access to these files, as they would be located on their local server, if replication works.

On that Partitions with the share I also have the Location A's home directories and many users Outlook PST files are located there. (Drive E). On the same Server (location A) I have my companies proprietary Software located on Drive D (same drive different partition).

Here is what gets me confused I have set a network share on Drive E called "Shared Files on loc A" I have set this as the DFS root on the Server in Location B I have a folder shared called "Shared Files from loc A" this is also set as a DFS root.

Now that the DFS is established and status has been checked and apparently working.

**My pst files on the home directories are bringing about save errors making outlook for users with their psts located here unusable, also my proprietary software doesn’t run properly, reports are not generating.

Why would DFS affect this area of the driver when I only specified it to share the specified folder.

After 1 day I was forced to turn it off since it had not replicated and the mail was affected.

Anyone have an idea what is going wrong?

 

[Jpoandl]

Location A is where my main files and documents are served and Location B needs to access them as well in relatively real time make changes as well."

DFS isn't designed to do what you want it to do. You can't have multiple users change the same DFS data and expect the data to be in tact.

DFS is meant for read-only data (installation media, for example). Or data that is edited by only one person (like home drives)

The limitation of DFS is that if multiple people edit the same document, whoever saves the document last will overwrite all of the other peoples changes.

Example:

a document called test.doc is within a DFS tree. There are two sites "SiteA" and "SiteB". DFS is replicating between sites. A user edits the test.doc document in SiteA at 12:00pm. Another user edits the test.doc document in SiteB at 12:00pm. UserA adds the word CHANGE at the end of the document and saves at 12:05pm. UserB adds the word "modify" and saves the document at 12:06pm.

When either user looks at the document again at 12:15pm, only the word MODIFY will be listed at the end of the test.doc document. This is because the last save WINS. User A had no idea that UserB was modifying the document. UserB had no idea that UserA was modifying the document. UserA thought that he updated the document and everything was cool...but when he checked the file later, it was changed.

So, you see there are some limitations to DFS...just be aware...

-later

Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please contact

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[nervous2]

Thanks for that breakdown, I wan't aware of this. Do you know if there is a software out that can do what I am asking? Someone suggested "double-take" I haven't tried it yet but I am interested in my options.

Thanks, Would FRS in windows do what I require?

 

[Jpoandl]

No FRS would not do what you require. DFS replication uses FRS. So, FRS would not help.

I'm can not recommend a software package for this....never had a need to implement this.

What your looking for is a software package that will LOCK a file when someone is editing it. This way is another person tries to edit the same doc (on a different share), the doc is locked. Only after the first person completes the edit and closes the document, will the second person be able to open it.

I don't know of any software that can do this...but maybe someone else does...



Joseph L. Poandl
MCSE 2003

If your company is in need of experts to examine technical problems/solutions, please contact

http://www.NJCOMPUTERNETWORKS.com

(Sales@njcomputernetworks.com)

 

[ITPangaeaArchitect]

Do NOT use DFS for .pst docs

DFS is built for mainly static docs

Yea I know theres not anything out there saying that, but trust me, I worked for MS supporting Directory services, which happens to encompass DFS

You will run into replication problems using DFS for documents that change constantly

FRS will not replicate data that is open (in use).

Double Take is a very good suggestion for you.

and you've already been told about the last writer wins topology for DFS
this is exactly why DFS is only recommended or data that remains mostly static

as far as .pst files...if a user has outlook open and outlook is using that .pst, then frs will not replicate that data because of a file in use error