Relevant error in the logs seems to be:
MainThread::DEBUG::2016-04-30 19:45:56,428::unified_persistence::46::root::(run) upgrade-unified-persistence upgrade persisting networks {} and bondings {}
MainThread::INFO::2016-04-30 19:45:56,428::netconfpersistence::187::root::(_clearDisk) Clearing /var/run/vdsm/netconf/nets/ and /var/run/vdsm/netconf/bonds/
MainThread::DEBUG::2016-04-30 19:45:56,428::netconfpersistence::195::root::(_clearDisk) No existent config to clear.
MainThread::INFO::2016-04-30 19:45:56,428::netconfpersistence::187::root::(_clearDisk) Clearing /var/run/vdsm/netconf/nets/ and /var/run/vdsm/netconf/bonds/
MainThread::DEBUG::2016-04-30 19:45:56,428::netconfpersistence::195::root::(_clearDisk) No existent config to clear.
MainThread::INFO::2016-04-30 19:45:56,428::netconfpersistence::131::root::(save) Saved new config RunningConfig({}, {}) to /var/run/vdsm/netconf/nets/ and /var/run/vdsm/netconf/bonds/
MainThread::DEBUG::2016-04-30 19:45:56,428::utils::671::root::(execCmd) /usr/bin/taskset --cpu-list 0-3 /usr/share/vdsm/vdsm-store-net-config unified (cwd None)
MainThread::DEBUG::2016-04-30 19:45:56,440::utils::689::root::(execCmd) SUCCESS: <err> = 'cp: cannot stat \xe2\x80\x98/var/run/vdsm/netconf\xe2\x80\x99: No such file or directory\n'; <rc> = 0
MainThread::DEBUG::2016-04-30 19:45:56,441::upgrade::51::upgrade::(_upgrade_seal) Upgrade upgrade-unified-persistence successfully performed
MainThread::DEBUG::2017-12-31 16:44:52,918::libvirtconnection::163::root::(get) trying to connect libvirt
MainThread::INFO::2017-12-31 16:44:53,033::netconfpersistence::194::root::(_clearDisk) Clearing /var/lib/vdsm/persistence/netconf/nets/ and /var/lib/vdsm/persistence/netconf/bonds/
MainThread::WARNING::2017-12-31 16:44:53,034::fileutils::96::root::(rm_tree) Directory: /var/lib/vdsm/persistence/netconf/bonds/ already removed
MainThread::INFO::2017-12-31 16:44:53,034::netconfpersistence::139::root::(save) Saved new config PersistentConfig({'ovirtmgmt': {'ipv6autoconf': False, 'nameservers': ['192.168.1.1', '8.8.8.8'], u'nic': u'eth0', 'dhcpv6': False, u'ipaddr': u'192.168.1.211', 'switch': 'legacy', 'mtu': 1500, u'netmask': u'255.255.255.0', u'bootproto': u'static', 'stp': False, 'bridged': True, u'gateway': u'192.168.1.1', u'defaultRoute': True}}, {}) to /var/lib/vdsm/persistence/netconf/nets/ and /var/lib/vdsm/persistence/netconf/bonds/
MainThread::DEBUG::2017-12-31 16:44:53,035::cmdutils::150::root::(exec_cmd) /usr/share/openvswitch/scripts/ovs-ctl status (cwd None)
MainThread::DEBUG::2017-12-31 16:44:53,069::cmdutils::158::root::(exec_cmd) FAILED: <err> = ''; <rc> = 1
MainThread::DEBUG::2018-02-16 23:59:17,968::libvirtconnection::167::root::(get) trying to connect libvirt
MainThread::INFO::2018-02-16 23:59:18,500::netconfpersistence::198::root::(_clearDisk) Clearing netconf: /var/lib/vdsm/staging/netconf
MainThread::ERROR::2018-02-16 23:59:18,501::fileutils::53::root::(rm_file) Removing file: /var/lib/vdsm/staging/netconf failed
Traceback (most recent call last):
File "/usr/lib/python2.7/site-packages/vdsm/common/fileutils.py", line 48, in rm_file
os.unlink(file_to_remove)
OSError: [Errno 21] Is a directory: '/var/lib/vdsm/staging/netconf'