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WLC is ARPing but will not receive answer from vlan-switch

Hi - this is my first posting in theese forums - hope I get it right

Setup: a procurve-vlan-switch (2915) is connected directly to a cisco-wlc (2504) on two ports.

     Port 1 on the wlc has the management- and apmanager-interface, untagged, connected to untagged port on procurveswitch.

     Port 2 on the wlc has a dynamic interface (vlan 100) connected to tagged (vlan100) port on the switch.

Port 1 I can ping, and everything works as it should, LAP connects and so on.

Port 2 I can't ping, and it will not let clients get an ip-address i the vlan100 segment.

     Wireshark tells me, that wlc sends arp-requests to the vlan-gateway on the procurve switch, and also that the switch replies in the same vlan (with tagged packets). But the WLC will not pick theese answers up and keeps ARPing for the gateway. Result is = no dhcp-answer to the clients.

Workaround: If I first ping from the wlc to the gateway, everything works for 5 minutes, i.e. I can ping the dynamic interface on the wlc and clients get ip-addresses, but when the arp-cache times out, everything goes black again.

BIG question: Can anyone help me with this? Why will the wlc not pick the arp-answer from the switch? The wlc asks with tagged packets and get tagged replies imediatly but will not listen


Nicholas Wolf Haamann

Everyone's tags (4)

Is there a reason you are

Is there a reason you are using two separate ports on the WLC?

Generally you would just create a Trunk port to the WLC and all traffic would pass over it.

The fact it works for 5 minutes makes me wonder if the WLC is somehow using the same MAC for both ports. What MAC addresses does the MAC address table on the HP switch show for both ports?

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