DHCP Relay bug? 4500G

[Josh-DPI]

We are using a 4500G as our Layer 3 switch and as a DHCP relay agent sending all DHCP requests to our Netware DHCP server.  Everything works fine for a couple days, but after a while clients can no longer get ip addresses.

The solution is to undo and then redo the DHCP SELECT RELAY command.  As soon as I do this on a given interface, everything works again for that VLAN.

It appears this has something to do with the 4500G keeping old entries in its ARP table, i.e. when the problem occurs there are usually multiple ip addresses listed for the same client MAC address.

Running the latest firmware on the switch.

Does anyone have any idea what is going on here?

[Fred_Mancen_1]

As a workaround you can define a lower aging time to the ARP table. I didn't face this problem before, but maybe it helps.

Regards

[Josh-DPI]

Thank you for the reply.  I have lowered the aging timer and will see if that helps.  I will report back my findings.

[Josh-DPI]

I am not sure why, but by lowering the aging timer from 20 minutes down to 15 minutes everything seems to be working fine.  Thanks again for the advice.

[Fred_Mancen_1]

Good to hear from you that the workaround worked well. Great.

Regards