We've got two HP2920-48G PoE switches connected together via a simple 1Gb cable (SW2:48 -> SW1:01), and then SW1:A1 fiber-channel to a central switch (SW9:A1).
All switches are untagged in the DEFAULT_VLAN (one /19 broadcast domain).
We have PoE Cisco phones plugged into SW2 and basically PCs/Macs plugged into SW1.
When we do a
clear arp in SW2, it seems to be able to ping everything in the network (as expected), but moments later it loses its ability to connect to certain IP addresses within the broadcast domain, including SW1 which is the switch it directly connects to. However, all the phones still work, and anything running ethernet still switches correctly. Its only the access to and from SW2:DEFAULT_VLAN address that seems to go bad.
We are not network engineers, but we know our way around switches a bit. What would be causing bad ARP entries, or why would
clear arp fix it momentarily, but only for the moment?