DOCUMENT:Q101473  08-AUG-2001  [winnt]
TITLE   :Replication Overview in the Windows NT Operating System
PRODUCT :Microsoft Windows NT
PROD/VER:WinNT:3.1,3.5,3.51,4.0
OPER/SYS:
KEYWORDS:kbnetwork

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The information in this article applies to:

 - Microsoft Windows NT Server version 3.1 
 - Microsoft Windows NT Workstation version 3.1 
 - Microsoft Windows NT Advanced Server, version 3.1 
 - Microsoft Windows NT Server versions 3.5, 3.51, 4.0 
 - Microsoft Windows NT Workstation versions 3.5, 3.51, 4.0 
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SUMMARY
=======

Windows NT supports replication to maintain specific, identical sets of files
and directories on different computers. Changes to information on one computer
is automatically replicated to other computers configured to receive those
changes. One common use for replication maintains identical login scripts for
all servers that process login requests in a domain. It can also be used to
replicate changes to other files, such as database files that are updated
regularly and must be duplicated exactly on other servers to maintain a copy of
the database.

MORE INFORMATION
================

To support replication, Windows NT requires an export server and an import
server. The export server must maintain the master copy of the files and
directories to replicate in an export directory (by default,
C:\WINNT\SYSTEM32\REPL\EXPORT). An export server can replicate directory trees
that contain as many as 32 subdirectories. After configuring a server to
replicate files, the EXPORT directory on the export server is automatically
shared as follows:

 - Repl$ as a hidden administrative share that allows the Administrators local
   group access with Full Control permission and the Replicator local group
   account access with Read permission.

Import servers can be computers with Windows NT Advanced Server, Windows NT, or
OS/2 LAN Manager 2.x servers. Import servers receive the master copy of the
files and directories from the export directory on the export server and place
them into an import directory (by default, C:\WINNT\SYSTEM32\REPL\IMPORT). After
configuring the system for replication, the IMPORT directory on each import
server is automatically shared as the IMPORT share that allows the Everyone
account access with Full Control permissions.

Replication goes from the export server to the import server(s), not the other
direction, unless an Advanced Server has been configured as both an export and
an import server. (A Windows NT workstation cannot be configured as an export
server.) At regular intervals, the import server establishes a session by
logging onto the export server. If the export server contains files or
directories that have been modified since the last update, these files are
replicated to the import server. If any files or directories have been deleted
from the import server or if new files have been created on the export server,
the export server replicates the files and directories not present and
resynchronizes the import directory.

Replication can occur between specific computers or between domains. If you
activate replication on the import server without specifying the name of a
computer or of a domain, the import server automatically replicates files from
the export server in its domain. An export server can also export files to a
specified domain. Any computer configured for import replication in the domain
receives any changes to files and directories. You can also configure
replication to occur between machines if a trust relationship exists between
their domains.

Additional Information:

See article Q104204 in the Microsoft Knowledge Base for more information.

Additional query words:

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Keywords          : kbnetwork 
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT351search kbWinNT350search kbWinNT400search kbWinNTW350 kbWinNTW350search kbWinNTW351search kbWinNTW351 kbWinNTW310 kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS350 kbWinNTS310 kbWinNTAdvSerSearch kbWinNTAdvServ310 kbWinNTS351search kbWinNTS350search kbWinNTS310search kbWinNT310Search kbWinNTW310Search
Version           : WinNT:3.1,3.5,3.51,4.0
Issue type        : kbinfo

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