In a nutshell, it appears that gerrit

https://git.opendaylight.org/gerrit/#/c/11319/

was merged to Helium and ovsdb code was not aware of it.

https://bugs.opendaylight.org/show_bug.cgi?id=1953

2015-02-20 12:35:59,648 | ERROR | pool-88-thread-1 | SouthboundHandler | 322 - org.opendaylight.ovsdb.openstack.net-virt - 1.0.2.Helium-SR2 | Exception caught in ProcessRowUpdate for node OVS|192.168.50.20:58698
java.lang.IllegalArgumentException: Supplied value "192.168.10.1" does not match any of the permitted patterns [^(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.)

([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])/(([0-9])|([1-2][0-9])|(3[0-2]))$]
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:119)[106:com.google.guava:14.0.1]
at org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.Ipv4Prefix.<init>(Ipv4Prefix.java:52)[192:org.opendaylight.yangtools.model.ietf-inet-types:2010.09.24.4_2-Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.providers.openflow13.services.ArpResponderService.programStaticArpEntry(ArpResponderService.java:76)[323:org.opendaylight.ovsdb.openstack.net-virt-providers:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.NeutronL3Adapter.programStaticArpStage2(NeutronL3Adapter.java:650)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.NeutronL3Adapter.programStaticArpStage1(NeutronL3Adapter.java:631)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.NeutronL3Adapter.programFlowsForNeutronRouterInterface(NeutronL3Adapter.java:430)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.NeutronL3Adapter.handleNeutronRouterInterfaceEvent(NeutronL3Adapter.java:183)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.NeutronL3Adapter.handleNeutronPortEvent(NeutronL3Adapter.java:157)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.NeutronL3Adapter.handleInterfaceEvent(NeutronL3Adapter.java:246)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.SouthboundHandler.handleInterfaceUpdate(SouthboundHandler.java:241)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.SouthboundHandler.processRowUpdate(SouthboundHandler.java:192)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.SouthboundHandler.processEvent(SouthboundHandler.java:358)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.EventDispatcherImpl.dispatchEvent(EventDispatcherImpl.java:92)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.EventDispatcherImpl.access$100(EventDispatcherImpl.java:28)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at org.opendaylight.ovsdb.openstack.netvirt.impl.EventDispatcherImpl$1.run(EventDispatcherImpl.java:55)[322:org.opendaylight.ovsdb.openstack.net-virt:1.0.2.Helium-SR2]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)[:1.7.0_75]
at java.util.concurrent.FutureTask.run(FutureTask.java:262)[:1.7.0_75]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)[:1.7.0_75]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)[:1.7.0_75]
at java.lang.Thread.run(Thread.java:745)[:1.7.0_75]