Bug 1878794

Summary: Azure: pod on the pod network cannot dial internal/external kube-apiserver load balancer
Product: OpenShift Container Platform Reporter: David Eads <deads>
Component: NetworkingAssignee: Ricardo Carrillo Cruz <ricarril>
Networking sub component: openshift-sdn QA Contact: zhaozhanqi <zzhao>
Status: CLOSED ERRATA Docs Contact:
Severity: high    
Priority: high CC: aarapov, aconstan, ffranz, nstielau, plarsen, sttts
Version: 4.6   
Target Milestone: ---   
Target Release: 4.6.0   
Hardware: Unspecified   
OS: Unspecified   
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Clone Of: Environment:
Last Closed: 2020-10-27 16:40:46 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description David Eads 2020-09-14 14:22:07 UTC
See https://prow.ci.openshift.org/view/gcs/origin-ci-test/logs/release-openshift-ocp-installer-e2e-azure-4.6/1305155086455934976

1. all kube-apiservers are functioning
2. the kube-apiserver (host network) can reach the internal/external load balancer consistently.
3. the openshift-apiserver (pod network) can access each kube-apiserver by direct IP
4. the openshift-apiserver (pod network) canNOT access the internal/external load balancer consistently.  Our connectivity check in must-gather shows connection interruptions every third attempt or so to the load balancers.

To summarize, the host network to LB access works.  The pod network to LB access does not work reliably.

Comment 1 Stefan Schimanski 2020-09-14 14:28:41 UTC
The logic around https://github.com/openshift/machine-config-operator/blob/master/templates/master/00-master/gcp/files/opt-libexec-openshift-gcp-routes-sh.yaml#L60 is missing in the Azure script. It matches the symptoms of non-local clients (e.g. pod network namespace) not being able to contact the LB 1/3 of the time.

Comment 5 zhaozhanqi 2020-09-23 06:27:17 UTC
Verified this bug on 4.6.0-0.nightly-2020-09-22-051033

rsh into openshift-apiserver pod and then try to curl the external LB 20 times,  all of them success 

oc rsh -n openshift-apiserver apiserver-74b6465579-6zdpc

for i in `seq 20` ; do curl -I --connect-timeout 5 https://api.zzhaoazu.qe.azure.devcluster.openshift.com:6443 -k ; done

Move this bug to 'verified'

Comment 6 Luis Sanchez 2020-10-02 14:11:32 UTC
*** Bug 1877880 has been marked as a duplicate of this bug. ***

Comment 9 errata-xmlrpc 2020-10-27 16:40:46 UTC
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.