OpenShift SDN connectivity fails with error “No Route to Host” on a particular node in RHOCP 4

Solution Verified - Updated 2025-07-22T06:11:11+00:00 -

Issue

A specific RHOCP node is experiencing network isolation, preventing it from reaching other pods via the cluster service IP range (172.30.x.x). This results to inter-pod communication failures and service access issues originating from the isolated node.
```
curl 172.30.x.x:<port> 
curl: (7) Failed to connect to 172.30.x.x port 27xx: No route to host
```

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