diff --git a/api/src/com/cloud/network/NetworkModel.java b/api/src/com/cloud/network/NetworkModel.java
index 811c792a0ff..4a09ea7d140 100644
--- a/api/src/com/cloud/network/NetworkModel.java
+++ b/api/src/com/cloud/network/NetworkModel.java
@@ -287,4 +287,6 @@ public interface NetworkModel {
     List<String[]> generateVmData(String userData, String serviceOffering, String zoneName,
                                   String vmName, long vmId, String publicKey, String password, Boolean isWindows);
 
+    String getValidNetworkCidr(Network guestNetwork);
+
 }
diff --git a/server/src/com/cloud/network/NetworkModelImpl.java b/server/src/com/cloud/network/NetworkModelImpl.java
index fbed85179b3..7caa328d444 100644
--- a/server/src/com/cloud/network/NetworkModelImpl.java
+++ b/server/src/com/cloud/network/NetworkModelImpl.java
@@ -2377,4 +2377,10 @@ public class NetworkModelImpl extends ManagerBase implements NetworkModel, Confi
     public ConfigKey<?>[] getConfigKeys() {
         return new ConfigKey<?>[] {MACIdentifier};
     }
+
+    @Override
+    public String getValidNetworkCidr(Network guestNetwork) {
+        String networkCidr = guestNetwork.getNetworkCidr();
+        return networkCidr == null ? guestNetwork.getCidr() : networkCidr;
+    }
 }
diff --git a/server/src/com/cloud/network/guru/GuestNetworkGuru.java b/server/src/com/cloud/network/guru/GuestNetworkGuru.java
index f6aeeab197f..74d774065c1 100644
--- a/server/src/com/cloud/network/guru/GuestNetworkGuru.java
+++ b/server/src/com/cloud/network/guru/GuestNetworkGuru.java
@@ -376,7 +376,7 @@ public abstract class GuestNetworkGuru extends AdapterBase implements NetworkGur
                 }
 
                 nic.setIPv4Address(guestIp);
-                nic.setIPv4Netmask(NetUtils.cidr2Netmask(network.getCidr()));
+                nic.setIPv4Netmask(NetUtils.cidr2Netmask(_networkModel.getValidNetworkCidr(network)));
 
                 nic.setIPv4Dns1(dc.getDns1());
                 nic.setIPv4Dns2(dc.getDns2());
diff --git a/server/src/com/cloud/network/router/NetworkHelperImpl.java b/server/src/com/cloud/network/router/NetworkHelperImpl.java
index 12ef0f9995e..9f5929356f4 100644
--- a/server/src/com/cloud/network/router/NetworkHelperImpl.java
+++ b/server/src/com/cloud/network/router/NetworkHelperImpl.java
@@ -743,7 +743,7 @@ public class NetworkHelperImpl implements NetworkHelper {
                 gatewayNic.setBroadcastType(guestNetwork.getBroadcastDomainType());
                 gatewayNic.setIsolationUri(guestNetwork.getBroadcastUri());
                 gatewayNic.setMode(guestNetwork.getMode());
-                final String gatewayCidr = guestNetwork.getCidr();
+                final String gatewayCidr = _networkModel.getValidNetworkCidr(guestNetwork);
                 gatewayNic.setIPv4Netmask(NetUtils.getCidrNetmask(gatewayCidr));
             } else {
                 gatewayNic.setDefaultNic(true);
diff --git a/server/src/com/cloud/network/router/NicProfileHelperImpl.java b/server/src/com/cloud/network/router/NicProfileHelperImpl.java
index 7575aad1b05..92a5915c4d5 100644
--- a/server/src/com/cloud/network/router/NicProfileHelperImpl.java
+++ b/server/src/com/cloud/network/router/NicProfileHelperImpl.java
@@ -127,7 +127,7 @@ public class NicProfileHelperImpl implements NicProfileHelper {
         guestNic.setBroadcastType(guestNetwork.getBroadcastDomainType());
         guestNic.setIsolationUri(guestNetwork.getBroadcastUri());
         guestNic.setMode(guestNetwork.getMode());
-        final String gatewayCidr = guestNetwork.getCidr();
+        final String gatewayCidr = _networkModel.getValidNetworkCidr(guestNetwork);
         guestNic.setIPv4Netmask(NetUtils.getCidrNetmask(gatewayCidr));
 
         return guestNic;
diff --git a/server/src/com/cloud/network/router/VirtualNetworkApplianceManagerImpl.java b/server/src/com/cloud/network/router/VirtualNetworkApplianceManagerImpl.java
index 43669d191eb..e0b08d1a70f 100644
--- a/server/src/com/cloud/network/router/VirtualNetworkApplianceManagerImpl.java
+++ b/server/src/com/cloud/network/router/VirtualNetworkApplianceManagerImpl.java
@@ -1535,7 +1535,7 @@ Configurable, StateListener<VirtualMachine.State, VirtualMachine.Event, VirtualM
                 }
             }
         } else if (dc.getNetworkType() == NetworkType.Advanced) {
-            final String cidr = guestNetwork.getCidr();
+            final String cidr = _networkModel.getValidNetworkCidr(guestNetwork);
             if (cidr != null) {
                 cidrSize = NetUtils.getCidrSize(NetUtils.getCidrNetmask(cidr));
                 dhcpRange = NetUtils.getDhcpRange(cidr);
diff --git a/server/test/com/cloud/network/MockNetworkModelImpl.java b/server/test/com/cloud/network/MockNetworkModelImpl.java
index f3d1f3827bd..4b4aebd1de0 100644
--- a/server/test/com/cloud/network/MockNetworkModelImpl.java
+++ b/server/test/com/cloud/network/MockNetworkModelImpl.java
@@ -901,4 +901,9 @@ public class MockNetworkModelImpl extends ManagerBase implements NetworkModel {
         return null;
     }
 
+    @Override
+    public String getValidNetworkCidr(Network guestNetwork) {
+        return null;
+    }
+
 }
diff --git a/server/test/com/cloud/vpc/MockNetworkModelImpl.java b/server/test/com/cloud/vpc/MockNetworkModelImpl.java
index 89a7ab7068b..6cd1ea1beaa 100644
--- a/server/test/com/cloud/vpc/MockNetworkModelImpl.java
+++ b/server/test/com/cloud/vpc/MockNetworkModelImpl.java
@@ -916,4 +916,9 @@ public class MockNetworkModelImpl extends ManagerBase implements NetworkModel {
         return null;
     }
 
+    @Override
+    public String getValidNetworkCidr(Network guestNetwork) {
+        return null;
+    }
+
 }