1 files changed, 55 insertions, 6 deletions

diff --git a/source3/nsswitch/winbindd_cm.c b/source3/nsswitch/winbindd_cm.c
index 3b83fde95b..5f477c78f7 100644
--- a/source3/nsswitch/winbindd_cm.c
+++ b/source3/nsswitch/winbindd_cm.c
@@ -140,31 +140,80 @@ static BOOL cm_ads_find_dc(const char *domain, struct in_addr *dc_ip, fstring sr
 */
 static BOOL cm_rpc_find_dc(const char *domain, struct in_addr *dc_ip, fstring srv_name)
 {
-	struct in_addr *ip_list = NULL;
+	struct in_addr *ip_list = NULL, exclude_ip;
 	int count, i;
 
-	if (!get_dc_list(False, domain, &ip_list, &count) && 
-	    !get_dc_list(True, domain, &ip_list, &count)) {
+	zero_ip(&exclude_ip);
+
+	/* Lookup domain controller name. Try the real PDC first to avoid
+	   SAM sync delays */
+
+	if (get_dc_list(True, domain, &ip_list, &count)) {
+		if (name_status_find(domain, 0x1c, 0x20, ip_list[0], srv_name)) {
+			*dc_ip = ip_list[0];
+			SAFE_FREE(ip_list);
+			return True;
+		}
+		/* Didn't get name, remember not to talk to this DC. */
+		exclude_ip = ip_list[0];
+		SAFE_FREE(ip_list);
+	}
+
+	if (!get_dc_list(False, domain, &ip_list, &count)) {
 		DEBUG(3, ("Could not look up dc's for domain %s\n", domain));
 		return False;
 	}
 
-	/* Pick a nice close server */
-	if (count > 1) {
-		qsort(ip_list, count, sizeof(struct in_addr), QSORT_CAST ip_compare);
+	/* Remove the entry we've already failed with (should be the PDC). */
+	for (i = 0; i < count; i++) {
+		if (ip_equal( exclude_ip, ip_list[i]))
+			zero_ip(&ip_list[i]);
 	}
 
+	/* Pick a nice close server */
+	/* Look for DC on local net */
 	for (i = 0; i < count; i++) {
 		if (is_zero_ip(ip_list[i]))
 			continue;
 
+		if (!is_local_net(ip_list[i]))
+			continue;
+		
 		if (name_status_find(domain, 0x1c, 0x20, ip_list[i], srv_name)) {
 			*dc_ip = ip_list[i];
 			SAFE_FREE(ip_list);
 			return True;
 		}
+		zero_ip(&ip_list[i]);
+	}
+
+	/*
+	 * Secondly try and contact a random PDC/BDC.
+	 */
+
+	i = (sys_random() % count);
+
+	if (!is_zero_ip(ip_list[i]) &&
+	    name_status_find(domain, 0x1c, 0x20,
+			     ip_list[i], srv_name)) {
+		*dc_ip = ip_list[i];
+		SAFE_FREE(ip_list);
+		return True;
 	}
+	zero_ip(&ip_list[i]); /* Tried and failed. */
+
+	/* Finally return first DC that we can contact using a node
+	   status */
+	for (i = 0; i < count; i++) {
+		if (is_zero_ip(ip_list[i]))
+			continue;
 
+		if (name_status_find(domain, 0x1c, 0x20, ip_list[i], srv_name)) {
+			*dc_ip = ip_list[i];
+			SAFE_FREE(ip_list);
+			return True;
+		}
+	}
 
 	SAFE_FREE(ip_list);