Encountering a NPE on 4.2.8. This is the first start after a 4.1 to 4.2 upgrade.

2019-07-05 15:36:56,912+08 ERROR [org.ovirt.engine.core.vdsbroker.CreateVDSCommand] (EE-ManagedThreadFactory-engine-Thread-45700) [64500cdd-b623-4bb1-a7a1-841
6b4e6723b] Failed to create VM: java.lang.NullPointerException
        at org.ovirt.engine.core.vdsbroker.builder.vminfo.LibvirtVmXmlBuilder.lambda$writeInterfaces$26(LibvirtVmXmlBuilder.java:1198) [vdsbroker.jar:]
        at java.util.Comparator.lambda$comparing$77a9974f$1(Comparator.java:469) [rt.jar:1.8.0_212]
        at java.util.TimSort.countRunAndMakeAscending(TimSort.java:355) [rt.jar:1.8.0_212]
        at java.util.TimSort.sort(TimSort.java:220) [rt.jar:1.8.0_212]
        at java.util.Arrays.sort(Arrays.java:1512) [rt.jar:1.8.0_212]
        at java.util.stream.SortedOps$SizedRefSortingSink.end(SortedOps.java:348) [rt.jar:1.8.0_212]
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:483) [rt.jar:1.8.0_212]
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:472) [rt.jar:1.8.0_212]
        at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151) [rt.jar:1.8.0_212]
        at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174) [rt.jar:1.8.0_212]
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) [rt.jar:1.8.0_212]
        at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:418) [rt.jar:1.8.0_212]
        at org.ovirt.engine.core.vdsbroker.builder.vminfo.LibvirtVmXmlBuilder.writeInterfaces(LibvirtVmXmlBuilder.java:1199) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.builder.vminfo.LibvirtVmXmlBuilder.writeDevices(LibvirtVmXmlBuilder.java:1045) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.builder.vminfo.LibvirtVmXmlBuilder.buildCreateVm(LibvirtVmXmlBuilder.java:254) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.vdsbroker.CreateBrokerVDSCommand.generateDomainXml(CreateBrokerVDSCommand.java:93) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.vdsbroker.CreateBrokerVDSCommand.createInfo(CreateBrokerVDSCommand.java:50) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.vdsbroker.CreateBrokerVDSCommand.executeVdsBrokerCommand(CreateBrokerVDSCommand.java:42) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.vdsbroker.VdsBrokerCommand.executeVdsCommandWithNetworkEvent(VdsBrokerCommand.java:123) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.vdsbroker.VdsBrokerCommand.executeVDSCommand(VdsBrokerCommand.java:111) [vdsbroker.jar:]
        at org.ovirt.engine.core.vdsbroker.VDSCommandBase.executeCommand(VDSCommandBase.java:73) [vdsbroker.jar:]
        at org.ovirt.engine.core.dal.VdcCommandBase.execute(VdcCommandBase.java:33) [dal.jar:]

This leads to Failed to run VM message. Any ideas?

Thanks

Richard Chan