демон централизованного управления Open Virtual Network (Open Virtual Network central control daemon)
ACTIVE-STANDBY FOR HIGH AVAILABILITY
You may run ovn-northd more than once in an OVN deployment. OVN
will automatically ensure that only one of them is active at a
time. If multiple instances of ovn-northd are running and the
active ovn-northd fails, one of the hot standby instances of
ovn-northd will automatically take over.