OVN has a built-in DNS server for assigning names to logical switch ports within an OVN logical network. When the RHOSP Networking service (Neutron) creates a VM's ports, it uses the built-in DNS server to add corresponding DNS data to the OVN north bound database. The DNS data is translated into logical flows in the southbound layer. As a result, ovn-controller can resolve DNS requests locally. The requests never leave the hypervisors.
Customers who use external DNS tools to handle VM DNS requests should consider disabling the built-in DNS feature.
RHOSP 16, 17 or later with the ML2/OVN mechanism driver.
Subscriber exclusive content
A Red Hat subscription provides unlimited access to our knowledgebase, tools, and much more.