found below in engine.log on engine VM
2018-05-17 11:03:57,739+01 ERROR [org.ovirt.engine.core.vdsbroker.monitoring.VmDevicesMonitoring] (EE-ManagedThreadFactory-engineScheduled-Thread-78) [6768004b] Exception:: org.springframework.dao.DataIntegrityViolationException: CallableStatementCallback; SQL [{call insertvmdevice(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)}]; ERROR: insert or update on table "vm_device" violates foreign key constraint "fk_vm_device_vm_static"
Detail: Key (vm_id)=(114581bb-7fef-4b08-8e3c-85dd5a9e680b) is not present in table "vm_static".
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2018-05-17 11:03:59,957+01 ERROR [org.ovirt.engine.core.bll.pm.FenceProxyLocator] (EE-ManagedThreadFactory-engineScheduled-Thread-44) [2bf8b18f] Can not run fence action on host 'ovirt', no suitable proxy host was found.
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2018-05-17 11:20:00,093+01 ERROR [org.ovirt.vdsm.jsonrpc.client.reactors.ReactorClient] (EE-ManagedThreadFactory-engine-Thread-2) [1a833057] Exception during connection
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2018-05-17 11:20:00,386+01 ERROR [org.ovirt.engine.core.vdsbroker.HostDevListByCapsVDSCommand] (EE-ManagedThreadFactory-engine-Thread-2) [1a833057] Command 'HostDevListByCapsVDSCommand(HostName = ovirt, VdsIdAndVdsVDSCommandParametersBase:{hostId='1a6a47e6-934e-43f7-ad5b-ba8f8ff8df99', vds='Host[ovirt,1a6a47e6-934e-43f7-ad5b-ba8f8ff8df99]'})' execution failed: java.net.UnknownHostException: ovirt: Name or service not known
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2018-05-17 11:20:03,287+01 ERROR [org.ovirt.vdsm.jsonrpc.client.reactors.ReactorClient] (EE-ManagedThreadFactory-engineScheduled-Thread-14) [] Exception during connection
2018-05-17 11:20:03,292+01 ERROR [org.ovirt.engine.core.vdsbroker.monitoring.HostMonitoring] (EE-ManagedThreadFactory-engineScheduled-Thread-14) [] Unable to RefreshCapabilities: UnknownHostException: ovirt
2018-05-17 11:20:03,294+01 INFO [org.ovirt.engine.core.vdsbroker.vdsbroker.GetCapabilitiesAsyncVDSCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-14) [] Command 'org.ovirt.engine.core.vdsbroker.vdsbroker.GetCapabilitiesAsyncVDSCommand' return value 'org.ovirt.engine.core.vdsbroker.vdsbroker.VDSInfoReturn@46e3da89'
2018-05-17 11:20:03,294+01 INFO [org.ovirt.engine.core.vdsbroker.vdsbroker.GetCapabilitiesAsyncVDSCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-14) [] HostName = ovirt
2018-05-17 11:20:03,297+01 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.GetCapabilitiesAsyncVDSCommand] (EE-ManagedThreadFactory-engineScheduled-Thread-14) [] Command 'GetCapabilitiesAsyncVDSCommand(HostName = ovirt, VdsIdAndVdsVDSCommandParametersBase:{hostId='1a6a47e6-934e-43f7-ad5b-ba8f8ff8df99', vds='Host[ovirt,1a6a47e6-934e-43f7-ad5b-ba8f8ff8df99]'})' execution failed: java.net.UnknownHostException: ovirt
2018-05-17 11:20:03,316+01 ERROR [org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector] (EE-ManagedThreadFactory-engineScheduled-Thread-15) [] EVENT_ID: VDS_BROKER_COMMAND_FAILURE(10,802), VDSM ovirt command GetCapabilitiesAsyncVDS failed: Connection issue ovirt
2018-05-17 11:20:03,317+01 ERROR [org.ovirt.engine.core.vdsbroker.monitoring.HostMonitoring] (EE-ManagedThreadFactory-engineScheduled-Thread-15) [] Unable to RefreshCapabilities: VDSNetworkException: VDSGenericException: VDSNetworkException: Connection issue ovirt
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and then above 5 error messages are keep repeating.
What does this mean? And how do I resolve this?