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Hi folks,
Happy New Year to start with.
My laptop is hooking up to a no-frills WLAN behind a Debian router
advertising a prefix using radvd. I've used this laptop for years in
similar situations, but this time I am seeing the kernel warn about
duplicate IPv6 addresses being detected:
IPv6: wifi: IPv6 duplicate address 2001:4428:29c:0:2ad2:44ff:fe8c:5bd detected!
I've unplugged/disconnected all other devices and yet the problem
persists. Hence I fired up tcpdump and captured the ICMPv6 packages.
And curiously, the laptop is sending two solicitations, one to the
multicast MAC address 33:33:ff:* and the other *to itself*!
Attached are the two packet dumps, and here's a diff between them,
with timestamps and identical stuff stripped:
-Frame 1: 78 bytes on wire (624 bits), 78 bytes captured (624 bits) on interface 0
+Frame 2: 78 bytes on wire (624 bits), 78 bytes captured (624 bits) on interface 0
[…]
-Ethernet II, Src: 28:d2:44:8c:05:bd, Dst: 33:33:ff:8c:05:bd
- Destination: 33:33:ff:8c:05:bd
- Address: 33:33:ff:8c:05:bd
- .... ..1. .... .... .... .... = LG bit: Locally administered address (this is NOT the factory default)
- .... ...1 .... .... .... .... = IG bit: Group address (multicast/broadcast)
+Ethernet II, Src: 28:d2:44:8c:05:bd, Dst: 28:d2:44:8c:05:bd
+ Destination: 28:d2:44:8c:05:bd
+ Address: 28:d2:44:8c:05:bd
+ .... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
+ .... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Correct me if I am wrong, but that second frame should not be sent,
right? Why would the node send a solicitation to itself?
Unfortunately, I have no idea where this is coming from. I've
disabled all bridges. This is Debian's 4.3.0-1-amd64 kernel
(4.3.3-1).
Do you have any clue what might be going on?
--
.''`. martin f. krafft <madduck@d.o> @martinkrafft
: :' : proud Debian developer
`. `'`
http://people.debian.org/~madduck
`- Debian - when you have better things to do than fixing systems
"most people become bankrupt through having invested too heavily in
the prose of life. to have ruined one's self over poetry is an
honour."
-- oscar wilde
--d6Gm4EdcadzBjdND
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment; filename="frame1.txt"
Frame 1: 78 bytes on wire (624 bits), 78 bytes captured (624 bits) on interface 0
Interface id: 0 (wifi)
Encapsulation type: Ethernet (1)
Arrival Time: Jan 3, 2016 10:25:50.168744045 NZDT
[Time shift for this packet: 0.000000000 seconds]
Epoch Time: 1451769950.168744045 seconds
[Time delta from previous captured frame: 0.000000000 seconds]
[Time delta from previous displayed frame: 0.000000000 seconds]
[Time since reference or fir