I have an Openshift 4.13 SNO set up and all was working well until yesterday. The timing seemed like after I installed and subsequently removed cert-manager, but all DNS requests from a container are coming back as the Openshift Node (192.168.2.11). After using a dnsutils container and running an nslookup on google.com, I get the following output:
# nslookup google.com
Server: 172.30.0.10
Address: 172.30.0.10#53
Non-authoritative answer:
Name: google.com.*cluster*.*domain*.com
Address: 192.168.2.11
Clearly, all lookups are coming back as subdomains of my cluster and pointing to my local node. I can verify this by every external request of my containers erroring out with the Application is not Available screen.
EDIT: One step closer to an answer, I think. If I remove my domain and cluster.domain.com from the search line of my /etc/resolv.conf dns resolution seems to work. I sadly don't know enough about DNS or Openshift/K8s to know what to do with this information