Server Doesn't Receive Broadcast Packets

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How can we check that what is root cause of a server doesn't receive broadcast packet (Including ARP)?
How can we find that how many broadcast packets are dropped?
There is no firewall or faulty physical link. tcpdump shows transmited broadcast packets but there is no received broadcast packet.



Sorry I missed the replies on your previous thread.

If you're packet capturing on the physical interface and don't see broadcast coming in, that's a problem outside the system. The OS can't control what it gets sent. If that's the situation then I'd look at the network switch, perhaps the switchport is in the wrong VLAN or similar.

Thanks for your response. Can be the problem related to driver or firmware? I couldn't find any advisory or update about the network adapter. As a temporary solution, I had to enable promiscuous mode on bond interface.

Ah, that's the same thing as you reported earlier.

Promisc Mode stops the NIC from performing MAC filtering. Usually a NIC will filter traffic which does not have the Destination MAC address of its own MAC and a few others, such as the Broadcast MAC and any subscribed Multicast MACs. Promisc Mode turns that hardware filtering off.

It's pretty strange for a NIC to disallow broadcast traffic like that. Networks need broadcast to work. It might be related to firmware or hardware. What sort of NIC is it? Are you using the in-kernel driver or a third-party driver?

There is compiled Intel driver that supplied by OS. I think, driver needs upgrade but firmware is not too old. We have 6 other servers but there is no problem about 5 servers. Just first and second servers have problem. HPE 562-SFP+ - FW: 10.4.3 - Driver: 2.1.14

The HPE 562SFP+ uses the i40e driver. There is a recent firmware update to these devices which requires a later driver shipped in RHEL 7.8. The driver will print a message about newer version of the NVM image into dmesg if that is the case. If you have any guests using SR-IOV make sure they are also using a compatible version of their iavf driver.

However, if all systems are the same (same BIOS, same NIC firmware, same kernel version, same driver, same config) then possibly you have one faulty device. You could swap a NIC with one from another system (make sure they go in the same slot so predictable naming doesn't change) and see if the fault stays with the system or the NIC.

Thank you Jamie for all your comments.