How to Add Site Information To Windows NT 4.0 Distributed File System Replica Members (281416)

SUMMARY

This article discusses how to add site information to Microsoft Windows NT 4.0 replica members.

When Distributed file system (Dfs) clients request referrals for a Dfs replica set, Microsoft Windows 2000 uses the client's Internet Protocol (IP) address to determine what site the client is in (this is accomplished by a Local Procedure Call (LPC) request to Netlogon which queries Active Directory. Active Directory then looks at the configured sites and calculates what site the provided IP address belongs to). Based on this site information, the list of replica members is reordered with servers in the same site as the client at the top of the list.

The client attempts to connect to the first server listed. This entire process works as previously described, except when Windows NT 4.0 replicas are present in the list. When you add a replica to a replica set, the computer hosting the share is queried for its site information. If the computer is a Windows 2000 server, this information is usually returned; however, if it is a Windows NT 4.0 computer, a remote procedure call (RPC) exception occurs since Windows NT 4.0 computers do not support this functionality.

Windows NT 4.0 computers are never ordered by site in the response to the client, since they do not contain site information. To add this functionality, the Dfsutil.exe utility has been modified so that site information for Windows NT 4.0 computers can be added or edited (as well as editing site information for other computers). Since the site information is only added at the time the replica is added to the replica set, it may be necessary to edit site information for servers if they are moved to a different site, or if a site is renamed.

MORE INFORMATION

To add site information to a Windows NT 4.0 computer you need to follow these steps:

Locate the computers to which you want to add site information. You can do this by first exporting the configuration. Run the following command:

dfsutil /view:\\dnsdomainname\dfsroot /export:path
You can view the output by opening the file in Microsoft Windows Notepad. You may observe the following output:

// uncomment the addroot lines if
// you want the script to create the root
// ADDROOT:dfsroot SERVER:DRNO SHARE:DfsROOT
// Load the dfs information
LOAD:\\hmss.com\dfsroot

// Link Information
LINK:Replica /MAP GUID:568B5D8077C9464DAB5AD1722A942BDC TIMEOUT:1
ADD:\\toddca5\replica
ADD:\\drno\replica
ADD:\\mrbig\replica
ADD:\\bugcheck\replica
// Site Information

SITE:bugcheck /MAP
ADD:Site48
SITE:MRBIG /MAP
ADD:HomeSite

SITE:DRNO /MAP
ADD:AnotherSite

// Save the dfs information
SAVE:
When you observe the preceding data you may observe that there is one replica with four members. Of those members, only three of them have site information, but not the Toddca5 server. This occurs because it is a Windows NT 4.0 server. To add site information to this server, you must run a script file, such as:

LOAD:\\hmss.com\dfsroot

SITE:TODDCA5 /MAP
ADD:Site48

SAVE:
The first line of the preceding script opens the configuration to the Dfs root and the last line saves the changes made to the site table. The site command expects two lines of data as previously shown. To import this script, you can use the following command: dfsutil /import:path to script file.
After you modify the Dfs configuration data with the import, you must reinitialize the Dfs service on each of the root servers. A Reinit operation can cause the server to reread the Dfs configuration data form the Active Directory. Until the configuration data is read by the server, it does not know about any of the modifications that have been made. The server can occasionally read the Dfs configuration data on its own. You can do this with the following command: dfsutil /reinit:servername.

NOTE: With any commands that are used with DfsUtil which have a /command:tag format, you must ensure that there is no space between the command and the colon (:) and the tag and the colon (:).