Description of problem: This bug is not related to core openshift sdn or ovn-kubernetes, it is with respect to the network operator. openshift-network-operator is crashing/restarting and is going though leader elections during the kube-apiserver rollout which takes around ~60 seconds with shutdown-delay-duration and gracefulTerminationDuration is now set to 0 and 15 seconds ( https://github.com/openshift/cluster-kube-apiserver-operator/pull/1168 and https://github.com/openshift/library-go/pull/1104 ).openshift-network-operator leader election timeout should be set to > 60 seconds to handle the downtime gracefully in SNO. Recommended lease duration values to be considered for reference as noted in https://github.com/openshift/enhancements/pull/832/files#diff-2e28754e69aa417e5b6d89e99e42f05bfb6330800fa823753383db1d170fbc2fR183: LeaseDuration=137s, RenewDealine=107s, RetryPeriod=26s. These are the configurable values in k8s.io/client-go based leases and controller-runtime exposes them. This gives us 1. clock skew tolerance == 30s 2. kube-apiserver downtime tolerance == 78s 3. worst non-graceful lease reacquisition == 163s 4. worst graceful lease reacquisition == 26s We can see that network-operator leader lease failures in the log: http://dell-r510-01.perf.lab.eng.rdu2.redhat.com/chaos/sno/openshift-network-operator/leader_election.log that ties to the restart:http://dell-r510-01.perf.lab.eng.rdu2.redhat.com/chaos/sno/openshift-network-operator/cerberus_cluster_state.log. The leader election can also be disabled given that there's no HA. Version-Release number of selected component (if applicable): 4.9.0-0.nightly-2021-08-01-132055 How reproducible: Always Steps to Reproduce: 1. Install a SNO cluster using the latest nightly payload. 2. Trigger kube-apiserver rollout/outage lasting for ~60 seconds - $ oc patch kubeapiserver/cluster --type merge -p '{"spec":{"forceRedeploymentReason":"ITERATIONX"}}' where X can be 1,2...n 3. Observe the state of network-operator. Actual results: network-operator is crashing/restarting and going through leader elections. Expected results: network-operator should handle the API rollout/outage gracefully. Additional info: Logs including must-gather: http://dell-r510-01.perf.lab.eng.rdu2.redhat.com/chaos/sno/openshift-network-operator/.
Verified this bug on 4.9.0-0.nightly-2021-08-17-183417 After patch kubeapiserver with oc patch kubeapiserver/cluster --type merge -p '{"spec":{"forceRedeploymentReason":"something2"}}' CNO pod did not restarted.
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 (Moderate: OpenShift Container Platform 4.9.0 bug fix and security update), 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/RHSA-2021:3759