From 3b797caab6583a6a7452a0eaf45fd7a670b4242c Mon Sep 17 00:00:00 2001
From: Aki Tuomi <cmouse@cmouse.fi>
Date: Mon, 9 Dec 2013 20:16:31 +0200
Subject: [PATCH] Check that the domain isn't already served by the new master

---
 pdns/packethandler.cc | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pdns/packethandler.cc b/pdns/packethandler.cc
index 0d2daa66e..e43802403 100644
--- a/pdns/packethandler.cc
+++ b/pdns/packethandler.cc
@@ -735,6 +735,7 @@ int PacketHandler::trySuperMaster(DNSPacket *p)
 
 int PacketHandler::trySuperMasterSynchronous(DNSPacket *p)
 {
+  DomainInfo di;
   Resolver::res_t nsset;
   try {
     Resolver resolver;
@@ -747,6 +748,14 @@ int PacketHandler::trySuperMasterSynchronous(DNSPacket *p)
     return RCode::ServFail;
   }
 
+  if (B.getDomainInfo(p->qdomain, di)) {
+    // maybe it is listed as master already
+    BOOST_FOREACH(string& master, di.masters) {
+      if (master == p->getRemote())
+        return RCode::NoError; // is already a master for this zone
+    }
+  }
+
   string account;
   DNSBackend *db;
   if(!B.superMasterBackend(p->getRemote(), p->qdomain, nsset, &account, &db)) {
-- 
2.40.0