Why would my router have different MAC addresses for IP and IPv6 transactions?

Posted by user329161 on Super User See other posts from Super User or by user329161
Published on 2014-06-04T02:51:03Z Indexed on 2014/06/04 3:27 UTC
Read the original article Hit count: 414

Filed under:

router

|

IPv6

|

mac-address

Today I was using tcpdump and I noticed my computer was having IPv6 traffic with a particular MAC address that I could not match with an IP using nmap or arping. After looking at the tcpdump logs a little more closely, I figured out it was another MAC address my router was using but exclusively for IPv6 traffic.

22:49:01.936830 90:0d:cb:ff:31:91 (oui Unknown) > 33:33:00:00:00:01 (oui Unknown), ethertype IPv6 (0x86dd), length 158: fe80::920d:cbff:feff:3191 > ip6-allnodes: ICMP6, router advertisement, length 104

Why would a router offer a different MAC address for IPv6?

© Super User or respective owner

Related posts about router

cisco 2911 router vs 2811 router

as seen on Server Fault - Search for 'Server Fault'
Just wondering if anyone has experience with the cisco 2911 or 2900 series routers. I understand it is newer and similar to the 2811 but more robust. The price difference is not that much more. I am trying to determine if I should go with the 29xx or 28xx series for a small-medium sized company… >>> More
Ubuntu 10.10 Ad-Hoc Setup (from Wireless Router, to Ubuntu Server/Desktop to Wireless Router)

as seen on Super User - Search for 'Super User'
Okay, so I know there are different approaches for this, but I will explain my story briefly before getting to the technical stuff. My fiancée and I are going through some financial issues (as I assume a lot of us are). We ended up having to move from our house and stay with some friends/family for… >>> More
linksys wrt54g router to a Cisco router?

as seen on Super User - Search for 'Super User'
This may be a strange question but I have no clue. I currently have a basic linksys wrt54g router fo9r my home network. I am considering getting a rack/cabinet and running a home server or 2 and hooking up my home network to it. If I were to do0 this I could pick up a cisco rack mounted router… >>> More
Prolink 5200 modem/router connected to Linksys WRT54GS wireless router

as seen on Super User - Search for 'Super User'
Hello does any one knows how to conect prolink 5200 single port modem/router with Linksys wireless router ......i dont know how to configerat these to togather >>> More
How to Reuse Your Old Wi-Fi Router as a Network Switch

as seen on How to geek - Search for 'How to geek'
Just because your old Wi-Fi router has been replaced by a newer model doesn’t mean it needs to gather dust in the closet. Read on as we show you how to take an old and underpowered Wi-Fi router and turn it into a respectable network switch (saving your $20 in the process). Image by mmgallan… >>> More

Related posts about IPv6

IPV6 auto configuration not working

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
In Windows 7, my computer can automatically get a IPV6 global address and use IPV6 network, but in Ubuntu Natty, I can't find out how to let stateless configuration work. My network is a university campus network,so I don't need tunnels. I think if one thing can silently and successfully be accomplished… >>> More
Fritz!Box IPv6-Address different than IPv6-Prefix

as seen on Server Fault - Search for 'Server Fault'
In my Fritzbox it states the following: IPv6-Adresse: 2a02:8070:600::14b6:c7******, Gültigkeit: 100465/86065s IPv6-Präfix: 2a02:8070:62c:3200::/56, Gültigkeit: 100464/86064s I am not able to connect to IPv6 Addresses from computers configured by the fritzbox, because they get an address with prefix… >>> More
Static IPv6 address advertising and IPv6 autoconfig in Debian/Ubuntu

as seen on Server Fault - Search for 'Server Fault'
I have a network that advertises IPv6 addresses through IPv6 autoconfig. To allow DNS lookups and to have fancy IP addresses, we setup "static" IPv6 addresses through /etc/network/interfaces: auto eth0 iface eth0 inet dhcp iface eth0 inet6 static address a:b:c:d:e::f netmask 64 Whenever… >>> More
HTG Explains: Are You Using IPv6 Yet? Should You Even Care?

as seen on How to geek - Search for 'How to geek'
IPv6 is extremely important for the long-term health of the Internet. But is your Internet service provider providing IPv6 connectivity yet? Does your home network support it? Should you even care if you’re using IPv6 yet? Switching from IPv4 to IPv6 will give the Internet a much larger pool… >>> More
Debian, 6rd tunnel, and connection troubles

as seen on Server Fault - Search for 'Server Fault'
Long story short I am having issues with IPv6 using a 6rd tunnel with my ISP, charter business. They offer a 6rd tunnel that I think I have properly set up, but the server doesn’t reply to every ipv6 request. When the server has the network interfaces idle with no traffic for about 10 minutes, then… >>> More