ciso 3825 ARP table problem

[dcmlfrog1]

Hi, All

Would you please help me with this problem?

The ARP table for my router has only one mac which is not the one of my computer. Also, it has multiple IPs. Would you please let me know why this is the case and how can I fix this?

Thank you.

22.16.32.1 00:24:14:60:C1:D9 24.86.180.1 00:24:14:60:C1:D9 24.86.184.1 00:24:14:60:C1:D9 24.86.184.102 60:2A:D0:8E:69:60 24.86.188.1 00:24:14:60:C1:D9 24.86.224.1 00:24:14:60:C1:D9 24.86.228.1 00:24:14:60:C1:D9 24.86.232.1 00:24:14:60:C1:D9 24.86.236.1 00:24:14:60:C1:D9 24.86.240.1 00:24:14:60:C1:D9 24.86.244.1 00:24:14:60:C1:D9 24.86.248.1 00:24:14:60:C1:D9 24.86.252.1 00:24:14:60:C1:D9 24.87.233.1 00:24:14:60:C1:D9 69.50.168.65 00:24:14:60:C1:D9 69.172.156.65 00:24:14:60:C1:D9

[Richard Burts]

You give us the output which shows two MAC addresses in the table. Would I be correct in assuming that the MAC address of 60:2A:D0:8E:69:60 is your PC and that 00:24:14:60:C1:D9 is the unknown device?

The vendor code of 00:24:14 is associated with some Cisco device. So I am guessing that your router is connected to some other Cisco device, and that the other Cisco device is sending ARP requests for many remote IP addresses. And that your router has enabled proxy arp.

As a start you might try show cdp neighbor on your router. If cdp is enabled and running on both devices then you should see the neighbor name and connection information.

One way to deal with this situation is to configure the Ethernet interface on your router with no ip proxy-arp. That may break some functionality on the other device. But when people start to complain about losing access to Internet then you will have confirmation about what the issue was.

HTH

Rick

[dcmlfrog1]

Hi, Rick

Thanks for your info.

Acturally the MAC address of 60:2A:D0:8E:69:60 is the mac for my Cisco router while my PC mac only shows in the local network table but not in the ARP/RARP table. I use Shaw cable service.

I live in a apartment and this is the only router in our home. I even shut down the wireless connection of the router already. I have no idea how other routers can connect to our router.

In addtion, how can Iconfigure the Ethernet interface on your router with no ip proxy-arp?

Thank youv very much.

Xin

[Richard Burts]

Xin

Now I am slightly puzzled and not quite sure how to respond. So first let me ask for some clarification. In your original post you included what appears to be ARP information. But it is not formatted in the way that a router does it. So where did this information come from?

Would you post the output of the command show arp on your router (so that I can see it as the router sees it). With this I may understand better what is going on and then know how to respond better to your question.

HTH

Rick

[Richard Burts]

Xin

I have done some more research and may have a partial answer. If this MAC address is your router

60:2A:D0:8E:69:60

It appears that this MAC address

00:24:14:60:C1:D9

is likely your cable box - probably from Scientific Atlanta/Cisco.

So now I would ask that you post part of the configuration for your router, especially any statements in the config that specify routing.

HTH

Rick