How the Autodisconnect Works in Windows NT

ID: Q138365

The information in this article applies to:

Microsoft Windows NT Workstation versions 3.5, 3.51, 4.0
Microsoft Windows NT Server versions 3.5, 3.51, 4.0
Microsoft Windows 2000 Professional
Microsoft Windows 2000 Server
Microsoft Windows 2000 Advanced Server

SUMMARY

This article documents the Windows NT local area network (LAN) related Autodisconnect parameter.

Windows NT uses two different Autodisconnect parameters; one for disconnecting Remote Access Service (RAS) connections and another for disconnecting LAN connections. The RAS Autodisconnect parameter is well documented in the Windows NT Server Remote Access Service manual on page 82, but the LAN version is undocumented. The only published reference to this Autodisconnect is in the Windows NT Resource Kit NT Registry Entries help file, in an overview of entries for the LanmanServer\Parameters section.

MORE INFORMATION

You can find the LAN Autodisconnect parameter in the registry under the subtree HKEY_LOCAL_MACHINE under the subkey:

\System\CurrentControlSet\Services\LanmanServer\Parameters

Purpose: The function is to disconnect idle sessions after a set number of minutes. The number of minutes can be set at a command prompt using the Net Config Server command. For example, to set the Autodisconnect value to 30 minutes:

Net Config Server /autodisconnect:30

The valid value range is -1 to 65535 minutes at the command line.

To disable Autodisconnect set it to: -1

Setting Autodisconnect to 0 does not turn it off and results in very fast disconnects, within a few seconds of idle time. (However, the RAS Autodisconnect parameter is turned off if you set it to a value of 0.)

NOTE: It is preferable to modify the LAN Autodisconnect directly in the registry. If you modify it at the command line, Windows NT may turn off its autotuning functions. For additional information, please see the following article in the Microsoft Knowledge Base:

ARTICLE-ID: Q128167
TITLE : Server Service Configuration and Tuning

The valid value range if you edit the LAN Autodisconnect parameter in the registry is 0 to 4294967295 (Oxffffffff). If you configure the Autodisconnect option to -1 at the command prompt, Autodisconnect is set to the upper value in the registry. This is approximately 8,171 years (not tested), which should be long enough to be the equivalent of turning Autodisconnect off.

Additional query words: prodnt

Keywords : kbnetwork ntras ntdomain ntconfig NTSrvWkst
Version : WINDOWS:2000; winnt:3.5,3.51,4.0
Platform : WINDOWS winnt
Issue type :