INFO: DsIsNTDSOnline Does Not Return Quickly as Expected (321029)

MORE INFORMATION

By default, the Directory Service functions use remote procedure call (RPC), regardless of the underlying network protocol. Because the Active Directory relies heavily on TCP/IP, a call to the DsIsNTDSOnline function will return immediately, regardless of the status of the targeted computer.

However, in some networking environments, other protocols in addition to TCP/IP may be installed on the client. In this scenario, DsIsNTDSOnline tries each network protocol in its binding order. If the targeted computer is not reachable or is not available, the control is returned to the calling process after DsIsNTDSOnline has tried all network protocols. The length of the delay also differs from one network protocol to another.

Steps to Reproduce the Problem

1. Replace MYCOMPUTER with the NetBIOS name of your computer as targetName in the following sample code. Note that you must link to Ntdsbcli.lib before you build the application.
   
   sample.c

   #include <windows.h>
   #include <stdio.h>
   #include <Ntdsbcli.h>
   
   #define MAX_LEN 100
   
   void main(void)
   {
       char targetName[MAX_LEN];
       BOOL status;
       HRESULT hr;
   
       /*---------------------------------------------------------
        * set the targetName to the NETBIOS name of your computer
        *---------------------------------------------------------*/ 
       sprintf(targetName, "%s", "MYCOMPUTER");
   
       printf("Checking machine: %s\n", targetName);
   
       printf("Before\n");
   	
       /*---------------------------------------------------------
        * Check if the AD is online
        *---------------------------------------------------------*/ 
       hr = DsIsNTDSOnline(targetName, &status);
   
       if  (hr != ERROR_SUCCESS) 
   	printf("DsIsNTDSOnline failed\n");
       else
   	printf("After\n");
   
   }
   					

2. Add IPX/SPX Protocol in your network protocol.
3. Run the application that you built in step 1.
   
   Notice that the length of time between the "Before" and "After" output is printed on the console.