ARP and Broadcast Packets Missing

Problem: A Linux box with Debian 9 (kernel 4.9) on a HP server with Intel i40e (X710) network cards, is not reachable from neighbor machines, because ARP does not work. Discussion: while testing with tcpdump ARP worked, but later ARP stopped working again. When tcpdump is used with “-p” (non promiscuous mode) you can see …

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ARP is not working on Cisco ASR 1001 X

Problem:┬áCisco ASR router is loosing connectivity to its directly attached Ethernet neighbors. In this situation interface status is still up, packets are going in and out on both ends, even IPv6 was still working. The actual problem was that the Cisco ASR was ignoring all ARP responses from its neighbors and the ARP┬átable to this …

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