1 files changed, 23 insertions, 0 deletions
diff --git a/cpp/src/IceDiscovery/PluginI.cpp b/cpp/src/IceDiscovery/PluginI.cpp
index e0e1a7f9849..cbc9a22c5f0 100644
--- a/cpp/src/IceDiscovery/PluginI.cpp
+++ b/cpp/src/IceDiscovery/PluginI.cpp
@@ -14,6 +14,8 @@
 #include <IceDiscovery/LocatorI.h>
 #include <IceDiscovery/LookupI.h>
 
+#include <Ice/Network.h>
+
 using namespace std;
 using namespace IceDiscovery;
 
@@ -72,6 +74,27 @@ PluginI::initialize()
     }
     int port = properties->getPropertyAsIntWithDefault("IceDiscovery.Port", 4061);
     string interface = properties->getProperty("IceDiscovery.Interface");
+    string defaultHost = properties->getProperty("Ice.Default.Host");
+    if(interface.empty() && !defaultHost.empty())
+    {
+        //
+        // Make sure the interface is an IP address, the UDP --interface option
+        // doesn't support DNS names.
+        //
+        IceInternal::ProtocolSupport protocol = ipv4 && !preferIPv6 ? IceInternal::EnableIPv4 : IceInternal::EnableIPv6;
+        try
+        {
+            IceInternal::Address address = IceInternal::getAddressForServer(defaultHost, 0, protocol, preferIPv6);
+            if(IceInternal::isAddressValid(address))
+            {
+                interface = IceInternal::inetAddrToString(address);
+            }
+        }
+        catch(const Ice::LocalException&)
+        {
+            // Ignore
+        }
+    }
 
     if(properties->getProperty("IceDiscovery.Multicast.Endpoints").empty())
     {