NetGetDCName function (lmaccess.h)

Article
02/22/2024

The NetGetDCName function returns the name of the primary domain controller (PDC). It does not return the name of the backup domain controller (BDC) for the specified domain. Also, you cannot remote this function to a non-PDC server.

Applications that support DNS-style names should call the DsGetDcName function. Domain controllers in this type of environment have a multi-master directory replication relationship. Therefore, it may be advantageous for your application to use a DC that is not the PDC. You can call the DsGetDcName function to locate any DC in the domain; NetGetDCName returns only the name of the PDC.

Syntax

NET_API_STATUS NET_API_FUNCTION NetGetDCName(
        LPCWSTR ServerName,
        LPCWSTR DomainName,
        LPBYTE  *Buffer
);

Parameters

ServerName

A pointer to a constant string that specifies the DNS or NetBIOS name of the remote server on which the function is to execute. If this parameter is NULL, the local computer is used.

DomainName

A pointer to a constant string that specifies the name of the domain. The domain name must be a NetBIOS domain name (for example, microsoft). NetGetDCName does not support DNS-style names (for example, microsoft.com). If this parameter is NULL, the function returns the name of the domain controller for the primary domain.

Buffer

Return value

If the function succeeds, the return value is NERR_Success.

If the function fails, the return value can be one of the following error codes.

Return code	Description
NERR_DCNotFound	Could not find the domain controller for the domain specified in the domainname parameter.
ERROR_BAD_NETPATH	The network path was not found. This error is returned if the computer specified in the servername parameter could not be found.
ERROR_INVALID_NAME	The name syntax is incorrect. This error is returned if the name specified in the servername parameter contains illegal characters.
ERROR_NOT_SUPPORTED	The request is not supported.

Remarks

No special group membership is required to successfully execute the NetGetDCName function.

Examples

The following code sample demonstrates how to retrieve the primary domain controller using the
NetGetDCName function. The sample calls NetGetDCName specifying the servername and domainname parameters. If the call succeeds, the code prints information out the name of the primary domain controller. Finally, the sample frees the memory allocated for the buffer where the domain controller name was returned.

#ifndef UNICODE
#define UNICODE
#endif

#include <stdio.h>
#include <stdlib.h>  // for _wtoi function
#include <assert.h>
#include <windows.h>
#include <lm.h>

// Need to link with netapi32.lib
#pragma comment(lib, "netapi32.lib")

int wmain(int argc, wchar_t * argv[])
{

    NET_API_STATUS nStatus;

    LPCWSTR lpServer = NULL;
    LPCWSTR lpDomain = NULL;

    LPCWSTR lpDcName = NULL;
    
    if (argc != 3 ) {
        wprintf(L"Usage: %ws <ServerName> <DomainName>\n",
                argv[0]);
        wprintf(L"     %ws Myserver Domain\n", argv[0]);
        exit(1);
    }

    lpServer = argv[1];
    lpDomain = argv[2];

    wprintf(L"Calling NetGetDCName with parameters\n");
    wprintf(L"    lpServer = %ws\n", lpServer);
    wprintf(L"    lpDomain = %ws\n", lpDomain);

    //
    // Call the NetGetDCName function
    //
    nStatus = NetGetDCName(lpServer, lpDomain, (LPBYTE *) &lpDcName);
    //
    // If the call succeeds,
    //
    if (nStatus == NERR_Success) {
        wprintf(L"NetGetDCName was successful\n", nStatus);
        wprintf(L"DC Name = %ws\n", lpDcName);
        // Need to free the returned buffer
        nStatus = NetApiBufferFree( (LPVOID) lpDcName);
        if (nStatus != NERR_Success)
            wprintf(L"NetApiBufferFree failed with error: %lu (0x%lx)\n",
                nStatus, nStatus);
    } else {
        wprintf(L"NetGetDCName failed with error: %lu (0x%lx)\n", nStatus,
                nStatus);
        wprintf(L"   Error = ");
        switch (nStatus) {
        case ERROR_INVALID_PARAMETER:
            wprintf(L"ERROR_INVALID_PARAMETER\n");
            break;
        case ERROR_NO_SUCH_DOMAIN:
            wprintf(L"ERROR_NO_SUCH_DOMAIN\n");
            break;
        case ERROR_NOT_SUPPORTED:
            wprintf(L"ERROR_NOT_SUPPORTED\n");
            break;
        case ERROR_BAD_NETPATH:
            wprintf(L"ERROR_BAD_NETPATH\n");
            break;
        case ERROR_INVALID_COMPUTERNAME:
            wprintf(L"ERROR_INVALID_COMPUTERNAME\n");
            break;
        case DNS_ERROR_INVALID_NAME_CHAR:
            wprintf(L"DNS_ERROR_INVALID_NAME_CHAR\n");
            break;
        case DNS_ERROR_NON_RFC_NAME:
            wprintf(L"DNS_ERROR_NON_RFC_NAME\n");
            break;
        case ERROR_INVALID_NAME:
            wprintf(L"ERROR_INVALID_NAME\n");
            break;
        case NERR_DCNotFound:
            wprintf(L"NERR_DCNotFound\n");
            break;
        case NERR_WkstaNotStarted:
            wprintf(L"NERR_WkstaNotStarted\n");
            break;
        case RPC_S_SERVER_UNAVAILABLE:
            wprintf(L"RPC_S_SERVER_UNAVAILABLE\n");
            break;
        case RPC_E_REMOTE_DISABLED:
            wprintf(L"RPC_E_REMOTE_DISABLED\n");
            break;
        default:
            wprintf(L"Other error, see Winerror.h or lmerr.h)\n");
            break;
        }
    }

    return nStatus;
}

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	lmaccess.h (include Lm.h)
Library	Netapi32.lib
DLL	Netapi32.dll

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