Description of problem:
PodNetworkConnectivityCheck reports "i/o timeout" for pod that are running

~~~
apiVersion: controlplane.operator.openshift.io/v1alpha1
kind: PodNetworkConnectivityCheck
metadata:
creationTimestamp: '2024-07-06T00:38:12Z'
generation: 3
managedFields:

• apiVersion: controlplane.operator.openshift.io/v1alpha1
  fieldsType: FieldsV1
  fieldsV1:
  'f:metadata':

failures:

• latency: 10.000398687s
  message: >-
  network-check-target-lxworker133: failed to establish a TCP connection
  to 10.128.41.44:8080: dial tcp 10.128.41.44:8080: i/o timeout
  reason: TCPConnectError
  success: false
  time: '2024-07-25T13:47:36Z'
• latency: 3.13174ms
  message: >-
  network-check-target-lxworker133: failed to establish a TCP connection
  to 10.128.83.6:8080: dial tcp 10.128.83.6:8080: connect: connection
  refused
  reason: TCPConnectError
  success: false
  time: '2024-07-06T01:32:52Z'
• latency: 4.517517ms
  message: >-
  network-check-target-lxworker133: failed to establish a TCP connection
  to 10.128.83.7:8080: dial tcp 10.128.83.7:8080: connect: connection
  refused
  reason: TCPConnectError
  success: false
  time: '2024-07-06T00:52:12Z'
• latency: 10.001391928s
  message: >-
  network-check-target-lxworker133: failed to establish a TCP connection
  to 10.128.83.7:8080: dial tcp 10.128.83.7:8080: i/o timeout
  reason: TCPConnectError
  success: false
  time: '2024-07-06T00:51:12Z'
• latency: 2.842981ms
  message: >-
  network-check-target-lxworker133: failed to establish a TCP connection
  to 10.128.83.7:8080: dial tcp 10.128.83.7:8080: connect: connection
  refused
  reason: TCPConnectError
  success: false
  time: '2024-07-06T00:50:12Z'
  outages:
• end: '2024-07-25T13:48:36Z'
  endLogs:
• latency: 8.988653ms
  message: >-
  network-check-target-lxworker133: tcp connection to
  10.128.41.44:8080 succeeded
  reason: TCPConnectime: '2024-07-25T13:47:36Z'
• end: '2024-07-06T01:33:52Z'
  endLogs:
• latency: 25.499411ms
  message: >-
  network-check-target-lxworker133: tcp connection to
  10.128.41.44:8080 succeeded
  reason: TCPConnect
  success: true
  time: '2024-07-06T01:33:52Z'
• latency: 3.13174ms
  message: >-
  network-check-target-lxworker133: failed to establish a TCP
  connection to 10.128.83.6:8080: dial tcp 10.128.83.6:8080: connect:
  connection refused
  reason: TCPConnectError
  success: false
  time: '2024-07-06T01:32:52Z'
  message: Connectivity restored after 1m0.001979942s
  start: '2024-07-06T01:32:52Z'
  startLogs:
• latency: 3.13174ms
  message: >-
  network-check-target-lxworker133: failed to establish a TCP
  connection to 10.128.83.6:8080: dial tcp 10.128.83.6:8080: connect:
  connection refused
  reason: TCPConnectError
  success: false
  time: '2024-07-06T01:32:52Z'
  ...
  successes:
• latency: 10.041793ms
  message: >-
  network-check-target-lxworker133: tcp connection to 10.128.41.44:8080
  succeeded
  reason: TCPConnect
  success: true
  time: '2024-08-02T15:24:36Z'
• latency: 22.147413ms
  message: >-
  network-check-target-lxworker133: tcp connection to 10.128.41.44:8080
  succeeded
  reason: TCPConnect
  success: true
  time: '2024-08-02T15:23:36Z'
• latency: 7.61857ms
  message: >-
  ...
  ~~~

When check the node sosreport we were not able to find the any logs also customer replied "
We haven't found any problems on the node, except for this outage warning. We checked the logs of application pods running on this node and no errors are seen. On the other hand, CPU, memory and network consumption look normal."

Since we do not see any type of problem in the nodes, or disconnections at the network level. What can be the cause of the issue

Version-Release number of selected component (if applicable): 4.12.35

How reproducible:

Steps to Reproduce:

1.

2.

3.

Actual results: Getting i/o timeout error in pncc

Expected results: Should not have any error. Since we do not see any type of problem in the nodes, or disconnections at the network level. What can be the cause of the issue

Additional info:

Please fill in the following template while reporting a bug and provide as much relevant information as possible. Doing so will give us the best chance to find a prompt resolution.

Affected Platforms:

Is it an

1. internal CI failure
2. customer issue / SD
3. internal RedHat testing failure

If it is an internal RedHat testing failure:

• Please share a kubeconfig or creds to a live cluster for the assignee to debug/troubleshoot along with reproducer steps (specially if it's a telco use case like ICNI, secondary bridges or BM+kubevirt).

If it is a CI failure:

• Did it happen in different CI lanes? If so please provide links to multiple failures with the same error instance
• Did it happen in both sdn and ovn jobs? If so please provide links to multiple failures with the same error instance
• Did it happen in other platforms (e.g. aws, azure, gcp, baremetal etc) ? If so please provide links to multiple failures with the same error instance
• When did the failure start happening? Please provide the UTC timestamp of the networking outage window from a sample failure run
• If it's a connectivity issue,
• What is the srcNode, srcIP and srcNamespace and srcPodName?
• What is the dstNode, dstIP and dstNamespace and dstPodName?
• What is the traffic path? (examples: pod2pod? pod2external?, pod2svc? pod2Node? etc)

If it is a customer / SD issue:

• Provide enough information in the bug description that Engineering doesn’t need to read the entire case history.
• Don’t presume that Engineering has access to Salesforce.
• Do presume that Engineering will access attachments through supportshell.
• Describe what each relevant attachment is intended to demonstrate (failed pods, log errors, OVS issues, etc).
• Referring to the attached must-gather, sosreport or other attachment, please provide the following details:
  • If the issue is in a customer namespace then provide a namespace inspect.
  • If it is a connectivity issue:
    • What is the srcNode, srcNamespace, srcPodName and srcPodIP?
    • What is the dstNode, dstNamespace, dstPodName and dstPodIP?
    • What is the traffic path? (examples: pod2pod? pod2external?, pod2svc? pod2Node? etc)
    • Please provide the UTC timestamp networking outage window from must-gather
    • Please provide tcpdump pcaps taken during the outage filtered based on the above provided src/dst IPs
  • If it is not a connectivity issue:
    • Describe the steps taken so far to analyze the logs from networking components (cluster-network-operator, OVNK, SDN, openvswitch, ovs-configure etc) and the actual component where the issue was seen based on the attached must-gather. Please attach snippets of relevant logs around the window when problem has happened if any.

• When showing the results from commands, include the entire command in the output.  
• For OCPBUGS in which the issue has been identified, label with “sbr-triaged”
• For OCPBUGS in which the issue has not been identified and needs Engineering help for root cause, label with “sbr-untriaged”
• Do not set the priority, that is owned by Engineering and will be set when the bug is evaluated
• Note: bugs that do not meet these minimum standards will be closed with label “SDN-Jira-template”
• For guidance on using this template please see
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