NetLogon Service Fails When Secure Channel Not Functioning (150518)

SYMPTOMS

The NetLogon service fails to start on a backup domain controller (BDC) with NetLogon error 3210 or 5721, whereas, in the system event logs of the primary domain controller (PDC,) the NetLogon service logs errors 5722 or At the same time, the Service Control Manager logs error 7023 on the BDC because the NetLogon service could not be started.

For each BDC, there is a discrete communication channel (the secure channel) with the PDC. The secure channel is used by the NetLogon service on the BDC and on the PDC in order to communicate.

The procedure described below resets the BDC secure channel using a single command line instead of many operations within the Server Manager. It requires the NETDOM utility provided with Windows NT 4.0 Resource Kit Supplement 2.

CAUSE

For the purpose of this article assume the following configuration:

   Domain = DOMAIN
   PDC    = DOMAINPDC
   BDC    = DOMAINBDC

When a BDC is part of a domain, a computer account is created (the computer account can be seen with Server Manager.) A default password is given to the computer account and the BDC stores the password in LSA secret storage $machine.acc. The password is then changed every seven days.

Each BDC maintains such an LSA secret, which is used by the NetLogon service in order to establish a secure channel. If the computer account's password and the LSA secret are not synchronized, the NetLogon service fails to start on the BDC with the following error message:

NETLOGON Event 3210

Failed to authenticate with \\DOMAINPDC, a Windows NT domain controller for domain DOMAIN.

If the computer account has been deleted, one of the following error messages are logged by the BDC NetLogon service:

NETLOGON Event 5721

The session setup to the Windows NT Domain Controller \\DOMAINPDC for the domain DOMAIN failed because the Windows NT Domain Controller does not have an account for the computer DOMAINBDC.

-or-

NETLOGON Event 5723

The session setup from the computer DOMAINBDC failed because there is no trust account in the security database for this computer. The name of the account referenced in the security database is DOMAINBDC$.

Similarly, the NetLogon service on the PDC logs the following error message when the password is not synchronized:

NETLOGON Event 5722

The session setup from the computer DOMAINBDC failed to authenticate. The name of the account referenced in the security database is DOMAINBDC$. The following error occurred:

Access is denied.

In all cases, the event data contains the error. For example, the error 0xC0000022 means the computer account's password is invalid, while the error 0xC000018B means the computer account has been deleted, and so on.

For more information on secure channels, please see the following article(s) in the Microsoft Knowledge Base:

131366Event Error 5712 with Status Access

142869Event ID 3210 and 5722 Appear When Synchronizing Entire Domain

149664Verifying Domain Netlogon

158148Domain Secure Channel Utility -- NLTEST.EXE

160324Event ID 5721 After Deleting Computer

RESOLUTION

WARNING: The solution included in this article has not been extensively tested in large installations. Microsoft cannot guarantee that modifications of domains as recommended herein will accomplish the objective described in this article under all circumstances and in all configurations.

The NETDOM command line utility makes it possible to reset the secure channel of the BDC. This can be very useful when the NetLogon service on the BDC cannot start due to a secure channel problem.

The BDC secure channel can be reset as follows:

   NETDOM BDC mybdc /RESET

The command above may be run on the PDC, BDC, or any member of the domain, provided that you are logged on as a user who is a member of the Domain Admins group. The output looks similar to the following:

   NetDom 1.2 @1997.
   Querying domain information on computer \\MYBDC ...
   The computer \\MYBDC is a domain controller of THEDOMAIN.
   Searching PDC for domain THEDOMAIN ...
   Found PDC \\THEPDC
   Verifying secure channel on \\MYBDC ...
   Verifying the computer account on the PDC \\THEPDC ...
   The computer account for \\MYBDC doesn't exist or has an invalid
   password.
   Resetting secure channel ...
   Changing computer account on PDC \\THEPDC ...
   Stopping service NETLOGON on \\MYBDC .... stopped.
   Starting service NETLOGON on \\MYBDC .... started.
   The BDC \\MYBDC secure channel was reset successfully.
   Logoff/Logon \\MYBDC to take modifications into effect.

The command above resets BDC secure channels only if required. If the password for the BDC secure channel was good, then you receive a message silimar to the following:

   NetDom 1.2 @1997.
   Querying domain information on computer \\MYBDC ...
   The computer \\MYBDC is a domain controller of THEDOMAIN.
   Searching PDC for domain THEDOMAIN ...
   Found PDC \\THEPDC
   Verifying secure channel on \\MYBDC ...
   Verifying the computer account on the PDC \\THEPDC ...
   Secure channel checked successfully.