Hi
I have realized we have a similar problem (Onehost sync fails during 5.12.0 upgrade) upgrading from 5.8.1 to 5.12.0 in CentOS 7.8
Also we can confirm the this command executed from any hyp:
echo '<MONITOR_CONFIGURATION><DATASTORE_LOCATION><![CDATA[/var/lib/one//datastores]]></DATASTORE_LOCATION><DB><CONNECTIONS><![CDATA[15]]></CONNECTIONS></DB><HOST_MONITORING_EXPIRATION_TIME><![CDATA[43200]]></HOST_MONITORING_EXPIRATION_TIME><IM_MAD><ARGUMENTS><![CDATA[-r 3 -t 15 -w 90 kvm]]></ARGUMENTS><EXECUTABLE><![CDATA[one_im_ssh]]></EXECUTABLE><NAME><![CDATA[kvm]]></NAME><SUNSTONE_NAME><![CDATA[KVM]]></SUNSTONE_NAME><THREADS><![CDATA[0]]></THREADS></IM_MAD><IM_MAD><ARGUMENTS><![CDATA[-r 3 -t 15 -w 90 lxd]]></ARGUMENTS><EXECUTABLE><![CDATA[one_im_ssh]]></EXECUTABLE><NAME><![CDATA[lxd]]></NAME><SUNSTONE_NAME><![CDATA[LXD]]></SUNSTONE_NAME><THREADS><![CDATA[0]]></THREADS></IM_MAD><IM_MAD><ARGUMENTS><![CDATA[-r 3 -t 15 -w 90 firecracker]]></ARGUMENTS><EXECUTABLE><![CDATA[one_im_ssh]]></EXECUTABLE><NAME><![CDATA[firecracker]]></NAME><SUNSTONE_NAME><![CDATA[Firecracker]]></SUNSTONE_NAME><THREADS><![CDATA[0]]></THREADS></IM_MAD><IM_MAD><ARGUMENTS><![CDATA[-c -t 15 -r 0 vcenter]]></ARGUMENTS><EXECUTABLE><![CDATA[one_im_sh]]></EXECUTABLE><NAME><![CDATA[vcenter]]></NAME><SUNSTONE_NAME><![CDATA[VMWare vCenter]]></SUNSTONE_NAME></IM_MAD><IM_MAD><ARGUMENTS><![CDATA[-r 3 -t 15 -w 90 dummy]]></ARGUMENTS><EXECUTABLE><![CDATA[one_im_sh]]></EXECUTABLE><NAME><![CDATA[dummy]]></NAME><SUNSTONE_NAME><![CDATA[Dummy]]></SUNSTONE_NAME><THREADS><![CDATA[0]]></THREADS></IM_MAD><LOG><DEBUG_LEVEL><![CDATA[3]]></DEBUG_LEVEL><SYSTEM><![CDATA[FILE]]></SYSTEM></LOG><MANAGER_TIMER><![CDATA[15]]></MANAGER_TIMER><MONITORING_INTERVAL_HOST><![CDATA[180]]></MONITORING_INTERVAL_HOST><NETWORK><ADDRESS><![CDATA[0.0.0.0]]></ADDRESS><MONITOR_ADDRESS><![CDATA[auto]]></MONITOR_ADDRESS><PORT><![CDATA[4124]]></PORT><PRIKEY><![CDATA[]]></PRIKEY><PUBKEY><![CDATA[]]></PUBKEY><THREADS><![CDATA[8]]></THREADS></NETWORK><PROBES_PERIOD><BEACON_HOST><![CDATA[30]]></BEACON_HOST><MONITOR_HOST><![CDATA[120]]></MONITOR_HOST><MONITOR_VM><![CDATA[30]]></MONITOR_VM><STATE_VM><![CDATA[5]]></STATE_VM><SYNC_STATE_VM><![CDATA[180]]></SYNC_STATE_VM><SYSTEM_HOST><![CDATA[600]]></SYSTEM_HOST></PROBES_PERIOD><VM_MONITORING_EXPIRATION_TIME><![CDATA[43200]]></VM_MONITORING_EXPIRATION_TIME><HOST_ID>0</HOST_ID></MONITOR_CONFIGURATION>' | /var/tmp/one/im/run_monitord_client kvm 0 localhost-kvm
Somehow has triggered the monitoring for the hyp with id 0 from the server, so in our case that hyp now is in enabled, but the rest of them are still in error state.