ARP request without response
Environment
Server with virtual IPs on one interface (in our case it was VLAN over bond, but it does not matter).
RHEL 5.10
Issue
In tcpdump there are only ARP requests in a form "Who has IP.AD.DR.ES? Tell SE.RD.DA.PI"
No response present for the combination of these two IPs, while other combinations work well.
Resolution
No issue, both IPs were on one server as virtuals for the one interface. Customer ran arping while taking capture.
Customer did not realised that when the two IPs are on the same server, no ARP is needed, ARP request was captured from the arping going out to switch, while switch did not send it back as it would be on the same port.
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