Switching back to my usual dns for ipv6 (Google's one,
2001:4860:4860::8844) solved my browsing issue.
But just to make sure, I then reopened the network settings: the same strange ipv4 addresses in my ipv6 dns configuration were back! Networking still works for now, but I fear the trouble will come back on next reboot.
The ipv4 tab has its expected settings.
/etc/resolv.conf file was pointing my isp own ipv6 dns server, I have removed them.
resolvconf package is not installed.
/etc/NetworkManager/system-connections/Wired connection 1 file looks fine.
[ethernet] duplex=full [connection] id=Wired connection 1 uuid=231ba09e-7c56-4fb3-9df2-37cc0c4202b0 type=ethernet timestamp=1480972453 [ipv6] method=auto dns=2001:4860:4860::8888;2001:4860:4860::8844; ignore-auto-dns=true ip6-privacy=2 [ipv4] method=auto dns=184.108.40.206;220.127.116.11; ignore-auto-dns=true
nm-connection-editor interface shows the right settings.
/etc/dhcp/dhclient.conf file does not contain any
Only the network configuration applet is wrong. I guess it is the
network-manager-gnome interface. Its version on my system is
0.9.10.0-2 according to synaptic.
My distribution is a Debian Jessie, unattended updates activated (stable channel of course, it would not be a Jessie anymore otherwise, backports enabled), using gnome.
I search a bit randomly in my hidden home folders if some local settings were related to networking just in case, but found nothing, including in
What else should I check for that issue please?
So the bad display looks like a bug, ipv6 addresses being displayed here as ipv4, using only first four bytes of them. Maybe this is just a display bug. But redefining my settings as I have done would then have overwritten the actual cause of the trouble...
I have reboot now, things still works for now (with display bug still here). No clue what was the actual trouble.
resolv.conf as I have done was undone at the next boot by the way, it was refilled with my isp ipv6 dns.)
Checking the nmap version on my system, it is
6.47-3+deb8u2. But anyway, the old bug you found about it does not look related, just similar as you say.