Comment 2 for bug 1661731

libvirt.log contains the following error messages before the error happened:

2017-02-03 18:50:35.818+0000: 16812: error : qemuMonitorIO:689 : internal error: End of file from monitor
2017-02-03 18:50:35.818+0000: 16812: debug : qemuMonitorIO:738 : Error on monitor internal error: End of file from monitor
2017-02-03 18:50:35.818+0000: 16812: debug : qemuMonitorIO:759 : Triggering EOF callback
[..]
2017-02-03 18:50:42.147+0000: 16816: error : qemuDomainAgentAvailable:3599 : argument unsupported: QEMU guest agent is not configured
[..]
2017-02-03 18:50:53.306+0000: 16814: error : virNetClientProgramDispatchError:177 : Cannot open log file: '/var/log/libvirt/qemu/instance-0000000b.log': Device or resource busy
[..]
2017-02-03 18:50:54.630+0000: 16812: error : qemuMonitorIORead:580 : Unable to read from monitor: Connection reset by peer