Description of problem: During conformance testing of OpenShift on IBM Cloud VPC test failures were experienced. Log analysis indicated etcd latency which triggers leader election. Version-Release number of selected component (if applicable): 4.10 How reproducible: Run conformance tests on an IPI deployed OpenShift cluster on IBM Cloud VPC. Steps to Reproduce: 1. Run conformance tests on an IPI deployed OpenShift cluster on IBM Cloud VPC. 2. 3. Actual results: Test failures (indicating etcd latency and etcd leader election). Expected results: Test success. Additional info: As a tactical action, recommend bumping leader election timeout (as is done for Azure). A bump to 2000 ms, should be sufficient. Once OpenShift IPI installer exposes options to influence etcd deployment AND IBM Cloud VPC offers better IOPS performance and more IOPS configuration options, the bump can be removed and timeout returned to default value. Code ref: https://github.com/openshift/cluster-etcd-operator/blob/161c61762ddbc8c5ca6723f56e2dba0e46c91da2/pkg/cmd/render/env.go#L64-L93
** A NOTE ABOUT USING URGENT ** This BZ has been set to urgent severity and priority. When a BZ is marked urgent priority Engineers are asked to stop whatever they are doing, putting everything else on hold. Please be prepared to have reasonable justification ready to discuss, and ensure your own and engineering management are aware and agree this BZ is urgent. Keep in mind, urgent bugs are very expensive and have maximal management visibility. NOTE: This bug was automatically assigned to an engineering manager with the severity reset to *unspecified* until the emergency is vetted and confirmed. Please do not manually override the severity. ** INFORMATION REQUIRED ** Please answer these questions before escalation to engineering: 1. Has a link to must-gather output been provided in this BZ? We cannot work without. If must-gather fails to run, attach all relevant logs and provide the error message of must-gather. 2. Give the output of "oc get clusteroperators -o yaml". 3. In case of degraded/unavailable operators, have all their logs and the logs of the operands been analyzed [yes/no] 4. List the top 5 relevant errors from the logs of the operators and operands in (3). 5. Order the list of degraded/unavailable operators according to which is likely the cause of the failure of the other, root-cause at the top. 6. Explain why (5) is likely the right order and list the information used for that assessment. 7. Explain why Engineering is necessary to make progress.
Can you please capture and attach the must-gather?
in conformance testing runs against IPI deployments on IBM Cloud VPC (using 4x16) we consistently see failures... here is a sample snippet {"level":"warn","ts":"2022-02-01T13:00:03.930Z","caller":"etcdserver/v3_server.go:815","msg":"waiting for ReadIndex response took too long, retrying","sent-request-id":10803993338213686342,"retry-timeout":"500ms"} {"level":"warn","ts":"2022-02-01T13:00:04.228Z","caller":"etcdserver/raft.go:369","msg":"leader failed to send out heartbeat on time; took too long, leader is overloaded likely from slow disk","to":"a38761c097c14cd7","heartbeat-interval":"100ms","expected-duration":"200ms","exceeded-duration":"638.378354ms"} {"level":"warn","ts":"2022-02-01T13:00:04.228Z","caller":"etcdserver/raft.go:369","msg":"leader failed to send out heartbeat on time; took too long, leader is overloaded likely from slow disk","to":"18358366a889f881","heartbeat-interval":"100ms","expected-duration":"200ms","exceeded-duration":"638.433744ms"} {"level":"warn","ts":"2022-02-01T13:00:04.228Z","caller":"etcdserver/util.go:166","msg":"apply request took too long","took":"858.984197ms","expected-duration":"200ms","prefix":"read-only range ","request":"key:\"/kubernetes.io/secrets/openshift-operator-lifecycle-manager/pprof-cert\" ","response":"range_response_count:1 size:5995"} {"level":"warn","ts":"2022-02-01T13:00:04.229Z","caller":"etcdserver/util.go:166","msg":"apply request took too long","took":"839.173911ms","expected-duration":"200ms","prefix":"read-only range ","request":"key:\"/kubernetes.io/namespaces/default\" serializable:true keys_only:true ","response":"range_response_count:1 size:53"} {"level":"warn","ts":"2022-02-01T13:00:04.229Z","caller":"etcdserver/util.go:166","msg":"apply request took too long","took":"839.37833ms","expected-duration":"200ms","prefix":"read-only range ","request":"key:\"/kubernetes.io/clusterroles/vpc-block-provisioner-role\" ","response":"range_response_count:1 size:933"} {"level":"warn","ts":"2022-02-01T13:00:04.231Z","caller":"etcdserver/util.go:166","msg":"apply request took too long","took":"801.893666ms","expected-duration":"200ms","prefix":"read-only range ","request":"key:\"/kubernetes.io/deployments/openshift-cluster-csi-drivers/ibm-vpc-block-csi-controller\" ","response":"range_response_count:1 size:8317"} {"level":"warn","ts":"2022-02-01T13:00:04.234Z","caller":"etcdserver/util.go:166","msg":"apply request took too long","took":"780.450358ms","expected-duration":"200ms","prefix":"read-only range ","request":"key:\"/kubernetes.io/health\" ","response":"range_response_count:0 size:6"}
Due to boot volume IOPS restrictions on IBM Cloud VPC (set to 3000) and no IPI installer option to influence ETCD deployment, we are left with bumped leader election timeout (tactically). IBM Cloud VPC does have boot volume IOPS options in roadmap (timeline TBD) and RH has plans to offer IPI installer options to influence ETCD deployment. Once we are able to leverage those features, the timeout bump can be returned to default.
Moving this to 4.11 since the fix will be going there initially.
@jnowicki.com, could u please try it again to confirm this issue fixed? thanks
@alray, you may reuse it for a new pr for 4.11, if you want to backport to 4.10, you may clone a new bug for 4.10 only
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 (Important: OpenShift Container Platform 4.11.0 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-2022:5069