RHEL8.6: Oracle instance down with "IPC Send timeout"

Issue

• UDP packets from sender does not reach the correct destination process on the receiver with incorrect port even though sender sends with correct port.
• Oracle instance down with "IPC Send timeout", for example:

2024-07-20T22:35:12.528535+09:00
IPC Send timeout to 1.0 inc 28 for msg type 106 from opid 165 -------------------------->> !!
2024-07-20T22:35:12.530140+09:00
IPC Send timeout: Terminating pid 165 osid 1335533 -------------------------->> !!
Process termination requested for pid 1335533 [source = rdbms], [info = 2] [request issued by pid: 1335533, uid: 300]
2024-07-20T22:36:32.892259+09:00
KILL SESSION for sid=(4174, 45779