Description of problem: after advertise L2 and EIP, pod cannot access external agnhost service by BGP router

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

How reproducible:

Steps to Reproduce:

1. setup BGP router (192.168.111.3) and external agnhost service(172.20.0.100)
2. advertise l2 and create l2 pod with EIP label

$ oc get pods -n udn-ns1 -owide
NAME         READY   STATUS    RESTARTS   AGE   IP            NODE                                 NOMINATED NODE   READINESS GATES
hello-pod1   1/1     Running   0          31m   10.128.0.28   worker-0.core.openshift-qe.sdn.com   <none>           <none>

3. create a EIP object and advertise it

$ oc get egressip
NAME       EGRESSIPS         ASSIGNED NODE                        ASSIGNED EGRESSIPS
egressip   192.168.111.200   worker-0.core.openshift-qe.sdn.com   192.168.111.200

4. verify pod to external agnhost service(ip: 172.20.0.100)

$ podman exec agnhost netstat -tuln
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       
tcp        0      0 :::8000                 :::*                    LISTEN      
udp        0      0 :::8081                 :::*      

$ oc exec -n udn-ns1 hello-pod1 -- curl 172.20.0.100:8000 --connect-timeout 5
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:--  0:00:05 --:--:--     0
curl: (28) Connection timeout after 5000 ms
command terminated with exit code 28

// tcpdump
sh-5.1# tcpdump -c 2 -nni enp2s0 host 172.20.0.100
dropped privs to tcpdump
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on enp2s0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
03:21:05.727485 IP 192.168.111.200.57934 > 172.20.0.100.8000: Flags [S], seq 3719986962, win 65280, options [mss 1360,sackOK,TS val 2638948065 ecr 0,nop,wscale 7], length 0
03:21:06.741189 IP 192.168.111.200.57934 > 172.20.0.100.8000: Flags [S], seq 3719986962, win 65280, options [mss 1360,sackOK,TS val 2638949080 ecr 0,nop,wscale 7], length 0
2 packets captured
2 packets received by filter
0 packets dropped by kernel

Actual results: pod cannot access external agnhost service by BGP router

Expected results: pod should access external agnhost service by BGP router

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
  OCPBUGS Template Training for Networking  components