[ovirt-users] oVirt self-Hosted engine- Hosted Engine failover issue

Hello all, i created two hosts in Default cluster. The Hosted Engine was installed in host1. Then i tried to live migrate hosted engine from host1 to host2 and it was OKAY. However, the hosted engine suddenly shut down for a while. Then, when the hosted engine worked again, i found that the hosted engine was located in host1. The problem is that since there is no vms inside these two hosts except hosted engine vm why the hosted engine will suddenly shutdown and auto migrate to host1? Since i am newer for ovirt self hosted engine if you guys want to read some log, would you give me the log path? I very appreciated with your help. Regards, Terry