I had oVirt 4.3 running on CentOS just fine for months. I did a yum update, and now the hosted engine isn't starting up. [root@nazgul qemu]# hosted-engine --vm-status --== Host nazgul.glamdring.offline (id: 1) status ==-- conf_on_shared_storage : True Status up-to-date : True Hostname : nazgul.glamdring.offline Host ID : 1 Engine status : {"reason": "bad vm status", "health": "bad", "vm": "down_unexpected", "detail": "Down"} Score : 0 stopped : False Local maintenance : False crc32 : fdab6d19 local_conf_timestamp : 2357 Host timestamp : 2357 Extra metadata (valid at timestamp): metadata_parse_version=1 metadata_feature_version=1 timestamp=2357 (Sat Jan 25 22:14:55 2020) host-id=1 score=0 vm_conf_refresh_time=2357 (Sat Jan 25 22:14:55 2020) conf_on_shared_storage=True maintenance=False state=EngineUnexpectedlyDown stopped=False timeout=Wed Dec 31 19:47:06 1969 Digging through the logs, I'm seeing an error that seems to be caused by an updated version of libvirt. Jan 25 22:13:05 nazgul libvirtd: 2020-01-26 03:13:05.879+0000: 4307: error : virCPUx86Compare:1785 : the CPU is incompatible with host CPU: Host CPU does not provide required features: md-clear In my /etc/libvirt/qemu/HostedEngine.xml, I'm thinking this line is the problem: <feature policy='require' name='md-clear'/> Looking at my cpu flags, md-clear ain't one of them: model name : Intel(R) Xeon(R) CPU E5-2670 0 @ 2.60GHz stepping : 7 microcode : 0x714 cpu MHz : 3000.061 cache size : 20480 KB physical id : 1 siblings : 16 core id : 7 cpu cores : 8 apicid : 47 initial apicid : 47 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm epb ssbd ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid xsaveopt dtherm ida arat pln pts spec_ctrl intel_stibp flush_l1d Any idea of how to remove that from the required CPU flags? Why is that needed?