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  1. OpenShift Bugs
  2. OCPBUGS-37695

Cannot reach to kubernetes.default.svc.cluster.local from workers of Hosted Cluster

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      This is a clone of issue OCPBUGS-37645. The following is the description of the original issue:

      Description of problem

      Debug into one of the worker nodes on the hosted cluster:

      oc debug node/ip-10-1-0-97.ca-central-1.compute.internal
      
      nslookup kubernetes.default.svc.cluster.local
      Server:         10.1.0.2
      Address:        10.1.0.2#53
      
      ** server can't find kubernetes.default.svc.cluster.local: NXDOMAIN
      
      curl -k https://172.30.0.1:443/readyz
      curl: (7) Failed to connect to 172.30.0.1 port 443: Connection refused
      
      sh-5.1# curl -k https://172.20.0.1:443/readyz
      ok

      Version-Release number of selected component (if applicable):

      4.15.20

      Steps to Reproduce:

      Unknown

      Actual results:

      Pods on a hosted cluster's workers unable to connect to their internal kube apiserver via the service IP.

      Expected results:

      Pods on a hosted cluster's workers have connectivity to their kube apiserver via the service IP.

      Additional info:

      Checked the "Konnectivity server" logs on Dynatrace and found the error below occurs repeatedly

      E0724 01:02:00.223151       1 server.go:895] "DIAL_RSP contains failure" err="dial tcp 172.30.176.80:8443: i/o timeout" dialID=8375732890105363305 agentID="1eab211f-6ea1-46ea-bc78-14d75d6ba325"
      
      E0724 01:02:00.223482       1 tunnel.go:150] "Received failure on connection" err="read tcp 10.128.17.15:8090->10.128.82.107:52462: use of closed network connection" 
      • Looks the konnectivity server is trying to establish a connection to 172.30.176.80:8443 but is timing out
      • also the 2nd error indicates that an existing network connection was closed unexpectedly

      Relevant OHSS Ticket: https://issues.redhat.com/browse/OHSS-36053

      Slack thread discussion

            agarcial@redhat.com Alberto Garcia Lamela
            openshift-crt-jira-prow OpenShift Prow Bot
            He Liu He Liu
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              Created:
              Updated:
              Resolved: