Thanks for assistance. Zipped engine starting from the day of upgrade attached.

oVirt engine runs on dedicated server, not hosted engine. Restart via SSH from oVirt Web GUI works.

I cut log to Aug 09 only.  On Friday Aug 6 we replaced switch in server rack, and therefore, there are a lot of non-relevant error messages.

vdsm service fail to start.

Aug 09 10:24:12 node14.mydomain.lv vdsmd_init_common.sh[4825]: vdsm: Running dummybr
Aug 09 10:24:13 node14.mydomain.lv vdsmd_init_common.sh[4825]: vdsm: Running tune_system
Aug 09 10:24:13 node14.mydomain.lv vdsmd_init_common.sh[4825]: vdsm: Running test_space
Aug 09 10:24:13 node14.mydomain.lv vdsmd_init_common.sh[4825]: vdsm: Running test_lo
Aug 09 10:24:13 node14.mydomain.lv systemd[1]: Started Virtual Desktop Server Manager.
Aug 09 10:24:16 node14.mydomain.lv sudo[7721]: pam_systemd(sudo:session): Failed to create session: Start job for unit user-0.slice failed with 'canceled'
Aug 09 10:24:16 node14.mydomain.lv sudo[7721]: pam_unix(sudo:session): session opened for user root by (uid=0)
Aug 09 10:24:16 node14.mydomain.lv sudo[7721]: pam_unix(sudo:session): session closed for user root
Aug 09 10:24:17 node14.mydomain.lv vdsm[6754]: WARN MOM not available. Error: [Errno 2] No such file or directory
Aug 09 10:24:17 node14.mydomain.lv vdsm[6754]: WARN MOM not available, KSM stats will be missing. Error: