Hi, dumb question again, but I am learning. I have 3 DHCP IP’s showing up on my network that can’t be identified. The mac addresses do not seem to be associated to any company to help identify the devices. In the meantime, I would like to block the these three IP’s or their mac address’s as I have no idea what they are. Unfortunately I have not been able to find directions on how to do this. Any help will be appreciated. Thanks, Bob Ivey
If you’re not concerned about security and just want a simple way to block a non-malicious user from eating bandwidth, you can create a DHCP reservation for these 3 MACs and assign them an invalid IP.
You can also find the rogue devices by looking at arp tables which will tell you which port the mac address is attached.
You can also Google Wireshark OUI Lookup which will tell you the vendor of the mac address. Maybe that’ll help you figure out what the devices are.
If you want to filter traffic based on mac address, the interfaces need to be in a bridge. Then in bridge > filters you can define rules.
IP > Firewall rules will only work if packets traverse subnets. So they can block those macs from connecting to the internet but can’t block those macs from connecting to other LAN hosts.
Bridge > filters only works between ports in a bridge. If an interface is a slave to another, no rules can stop the flow of packets.
Thanks so much for your great reply. It actually solved the primary problem of identifying what the three IP’s are associated with. I had tried quite a few MAC lookup’s with not results. Had not tried Wireshark lookup until your suggestion. They turned out to be from the my Directv genie system. I did’t suspect the Directv system since the clients from the main genie box do not have network connections on the three sub boxes. The gain their IP’s over the coax cable that delivers programming from the main box and I was previously under the impression that they were on a different subnet. Now that I know what they really are I don’t have to worry about devices on my network that I can’t identify. Your help was invaluable in getting to the bottom of this problem. Thank-you so much.