Description of problem: On ovirt e2e tests we noticed errors on master/worker journal due to: dial tcp: lookup api-int.ovirt1X.gcp.devcluster.openshift.com on 192.168.21X.1:53: no such host" see: 1. https://bugzilla.redhat.com/show_bug.cgi?id=1846529#c18 2. ovirt17-kcphn-worker-0-c2rd4 journal on CI job https://prow.ci.openshift.org/view/gs/origin-ci-test/logs/release-openshift-ocp-installer-e2e-ovirt-4.6/1302427462155636736: cat journal|grep "api-int.*1:53: no such host"|wc -l 945 On ovirt CI 192.168.21X.1 is the upstream DNS, and api-int is resolveable only on CoreDNS. That means that at some points the coreDNS is not available and the node tries to use the Upstream DNS. Additional thoughts: The NetworkManager-resolve-prepender is responsible for adding the coredns to the resolv.conf. As we can see on https://bugzilla.redhat.com/show_bug.cgi?id=1846529#c28 """ by looking at ovirt11-wz8kt-worker-0-5686p workers journal [0]: during this lookup failure we can see : # cat workers-journal | grep nm-dispatcher | grep 'worker-0-5686p' | grep resolv-prepender Aug 16 02:45:15.570577 ovirt11-wz8kt-worker-0-5686p nm-dispatcher[302731]: <13>Aug 16 02:45:15 root: NM resolv-prepender triggered by ens3 dhcp4-change. Aug 16 02:45:17.726649 ovirt11-wz8kt-worker-0-5686p nm-dispatcher[302731]: <13>Aug 16 02:45:17 root: NM resolv-prepender: Prepending 'nameserver 192.168.211.118' to /etc/resolv.conf (other nameservers from /var/run/NetworkManager/resolv.conf) """ It takes 2s to finish, at the begining of the script we copy /var/run/NetworkManager/resolv.conf to /etc/resolv.conf that means that in those 2 seconds we have the wrong DNS and that will lead to unexpected problems.
*** Bug 1876215 has been marked as a duplicate of this bug. ***
We don't see the issue occurring at CI anymore. Verified in OCP 4.6.0-0.nightly-2020-09-17-031725 with RHV 4.4.0.3-1.el8
*** Bug 1846529 has been marked as a duplicate of this bug. ***
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (OpenShift Container Platform 4.6 GA Images), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2020:4196