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If a device has same mac address but different IP on home router,

is this some sort of error or hacking? What is going on?

I can't attach a pic so I've listed below. Computer name for second doesn't show. Just blank.


Computer Name Mac Address IP

David 11:22:33:44:55

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closed as off topic by longneck, mulaz, Hennes, Mark Henderson Mar 1 '13 at 1:07

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Can you clarify this? Do you have two different devices that actually have the same MAC address? This is not supposed to happen, but it is made more likely with virtual machines, bridge interfaces, and various other kinds of interfaces with made-up MAC addresses rather than burned-in MAC addresses. – Celada Mar 1 '13 at 0:36
No I just have 4 computers connected, but I saw 5 connections. It turns out there are 2 connections with same MAC address but different IP. – rissn Mar 1 '13 at 0:38
I don't think I have devices with two same mac address. I am just wondering if I was hacked(aka arp spoofing hack ) – rissn Mar 1 '13 at 0:38
"there are 2 connections with same MAC address but different IP". It sounds like you simply have a device on your network that has 2 IP addresses. So what's the problem? – Celada Mar 1 '13 at 0:42
I am just wondering if I am being hacked. Never had this problem occur on router before so... – rissn Mar 1 '13 at 0:43

Yes, it is possible to have more then one IP on one interface (with one MAC address).

There is also a bug on some Android devices, where they "forget" to renew a DHCP lease, but request a new one (and get a new IP) every now and then, while they keep an old IP address active.

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So I am not being hacked? It's actually a computer, not android, I believe. Can this occur on iphone devices as well? – rissn Mar 1 '13 at 0:39
It can happen on every device, and because of many reasons. Try pinging the device, and/or seeing where it's connected from, to see what's there. – mulaz Mar 1 '13 at 0:41
I see. Can this a example of arp spoofing? Meaning am I being hacked? The second connection with same Mac but diff IP has no computer name(blank). – rissn Mar 1 '13 at 0:42
It is possible, but it is impossible to tell just from that log data. – mulaz Mar 1 '13 at 0:48
hmm so it's not just one instances of error? – rissn Mar 1 '13 at 0:49

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