CCR1009-8G-1S and "ghost" IP's on VLAN

RouterOS General
1

A few days ago I replaced an old DrayTek 3900 with an CCR1009-8G-1S at one of my customers. Everything started to runner much better but two days ago we found a problem. When I run a network scan application (in this case Advanced IP Scanner) I start to see the all range of IP’s (free IP’s) pointing to the router mac address. If I ping any of the IP that I know don’t exist I get no response.

The problem is that the customer have some computers with fixed IP not used by any other device, that are reporting a duplicated IP and not connecting to the network. There are other devices with IP (special devices to control water pumps) that are reporting a duplicated IP and show the router MAC address as the duplicated IP device. This device can’t connect to the network. I have enabled proxy-arp on the VLAN where this happen because I need VPN access.

My setup is like this: eth5 - WAN, eth6 LAN. On eth6 I configured 6 VLAN’s. For each VLAN I gave an Address, but only configured a DHCP to 2 VLAN’s, one if for wifi and the other one is for eth1 with the default router IP. Current RouterOS is 6.31.

Any help will be apreciated.

2

First thing I’d do is using bugfix ROS version, also make sure firmware is up to date.

A reset to no defaults then reloading the configuration after that would be good practice.

If problem persists, do a Tools > Ip Scan? what does it report?

You could also try using src-nat instead of proxy-arp for VPN users, to see if the problem is related to that.