Description of problem:

OVN-Kubernetes is not correctly applying the configured EgressIP to traffic originating from a specific customer namespace. The traffic is expected to use a designated EgressIP when exiting through the assigned gateway node, but it is observed to be using a different EgressIP instead. This incorrect EgressIP assignment leads to a loss of external connectivity.

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

OCP Cluster version is 4.16.24

How reproducible:

The issue is consistently reproducible in the affected environment. All attempts to route traffic through the intended EgressIP result in the same incorrect behavior.

Steps to Reproduce:

1.  In a namespace configured with multiple EgressIPs assigned to different gateway nodes, attempt to route traffic through one of the specified EgressIPs.

2. Deploy a test pod and attempt to establish external connectivity.

3. Monitor network traffic on the designated gateway node.

Actual results:

1. External connectivity from the test pod fails.

2. Packet captures on the gateway node show outbound traffic using an incorrect source IP, which is an EgressIP assigned to a different gateway node.

Expected results:

1. External connectivity is successful.

2. Outbound traffic from the test pod uses the source IP that is correctly assigned to the gateway node.

Additional info:

Sharing as private notes as data is customer specific. However in generic terms:

This issue was identified in the Project_name namespace.

The EgressIP IP1, assigned to a specific gateway node, is being ignored. Traffic is instead using IP2, which is assigned to a different gateway node.

A test with a newly created EgressIP also failed, with traffic continuing to use IP2.

Attached in the case# 04240388 are Cluster Must-Gather, sosreports from the gateway nodes, pcaps showing the incorrect source IP, and namespace inspect files.