ARP Reply Only

RouterOS General
1

On a V2.8.11 router, I am trying to stop static IP addresses being used on a network with a DHCP server. To do this, I have set the DHCP server to Add ARP for leases (all leases are static) and set the interface to ARP reply only.

This seems to work, stopping static assignment of IP and DNS settings on a host, but every so often (maybe half of lease time) I loose connectivity between the hosts and the router, for about fifteen seconds.

Can anyone explain what is happening?

Thanks,
Guy

2

OK, worked it out for myself.

In case anyone else has the same problem, one of the hosts was behind a wireless bridge which does MAC address translation. The DHCP server was adding an ARP entry for the hosts MAC, not the wireless bridge MAC. So, once traffic started to move between the host and the router there was no ARP entry for the bridge’s MAC address.

Guy