DNS Resolver not functioning

Hi all,

I’ve read the forum before posting and could’nt find any explanation.

Here is my problem : i cannot access internet through domain names. It worked and after a reboot, it doesn’t.

Here are the things i have checked :

  • wifi or ethernet networks are OK, i use them on another computer
  • $ping 8.8.8,8 is OK while $ping example.com returns “temporary failure in name resolution” (from french to english)
  • i can surf with a live key OS like Tails
  • Networks are recognized on the NetworkManager GUI and tells me i am connected to wifi or ethernet

So i am suspecting a local DNS resolver issue.

Below some system information that may be of some interest :

$sudo systemctl status NetworkManager
● NetworkManager.service - Network Manager
     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; enabled; preset: disabled)
     Active: active (running) since Thu 2022-10-13 18:45:09 CEST; 54min ago
       Docs: man:NetworkManager(8)
   Main PID: 773 (NetworkManager)
      Tasks: 3 (limit: 8828)
     Memory: 18.3M
        CPU: 6.944s
     CGroup: /system.slice/NetworkManager.service
             └─773 /usr/bin/NetworkManager --no-daemon

oct. 13 18:53:22 thinkpad NetworkManager[773]: <info>  [1665680002.1712] dhcp4 (enp0s31f6): canceled DHCP transaction
oct. 13 18:53:22 thinkpad NetworkManager[773]: <info>  [1665680002.1713] dhcp4 (enp0s31f6): activation: beginning transaction (timeout in 45 seconds)
oct. 13 18:53:22 thinkpad NetworkManager[773]: <info>  [1665680002.1714] dhcp4 (enp0s31f6): state changed no lease
oct. 13 18:53:22 thinkpad NetworkManager[773]: <info>  [1665680002.1721] dhcp6 (enp0s31f6): canceled DHCP transaction
oct. 13 18:53:22 thinkpad NetworkManager[773]: <info>  [1665680002.1722] dhcp6 (enp0s31f6): activation: beginning transaction (timeout in 45 seconds)
oct. 13 18:53:22 thinkpad NetworkManager[773]: <info>  [1665680002.1723] dhcp6 (enp0s31f6): state changed no lease
oct. 13 18:53:22 thinkpad NetworkManager[773]: <info>  [1665680002.2143] policy: set 'cequejevois-wifi' (wlp4s0) as default for IPv4 routing and DNS
oct. 13 19:14:11 thinkpad NetworkManager[773]: <info>  [1665681251.2142] agent-manager: agent[3b28c8b415d7e3b9,:1.63/org.gnome.Shell.NetworkAgent/1000]: agent registered
oct. 13 19:20:31 thinkpad NetworkManager[773]: <info>  [1665681631.9671] agent-manager: agent[45b34c68563e3056,:1.184/org.gnome.Shell.NetworkAgent/120]: agent registered
oct. 13 19:20:45 thinkpad NetworkManager[773]: <info>  [1665681645.4523] agent-manager: agent[3b28c8b415d7e3b9,:1.222/org.gnome.Shell.NetworkAgent/1000]: agent registered
$cat /etc/resolv.conf
# Generated by NetworkManager
nameserver ::1
$inxi -Fxxxz
System:
  Kernel: 5.9.16-1-MANJARO arch: x86_64 bits: 64 compiler: gcc v: 10.2.0
    Desktop: GNOME v: 42.4 tk: GTK v: 3.24.34 wm: gnome-shell dm: GDM v: 42.0
    Distro: Manjaro Linux base: Arch Linux
Machine:
  Type: Laptop System: LENOVO product: 20F5S04B00 v: ThinkPad X260
    serial: <superuser required> Chassis: type: 10 serial: <superuser required>
  Mobo: LENOVO model: 20F5S04B00 v: SDK0J40705 WIN
    serial: <superuser required> UEFI-[Legacy]: LENOVO v: R02ET70W (1.43 )
    date: 01/28/2019

[...]

Network:
  Device-1: Intel Ethernet I219-V vendor: Lenovo driver: e1000e v: kernel
    port: N/A bus-ID: 00:1f.6 chip-ID: 8086:1570 class-ID: 0200
  IF: enp0s31f6 state: down mac: <filter>
  Device-2: Broadcom BCM4356 802.11ac Wireless Network Adapter
    vendor: Lenovo driver: brcmfmac v: kernel pcie: speed: 2.5 GT/s lanes: 1
    bus-ID: 04:00.0 chip-ID: 14e4:43ec class-ID: 0280
  IF: wlp4s0 state: up mac: <filter>
  IF-ID-1: ipv6leakintrf0 state: unknown speed: N/A duplex: N/A
    mac: <filter>

[...]

Info:
  Processes: 213 Uptime: 59m wakeups: 15 Memory: 7.21 GiB used: 1.04 GiB
  (14.5%) Init: systemd v: 251 default: graphical Compilers: gcc: 12.2.0
  clang: 14.0.6 Packages: pm: pacman pkgs: 1607 Shell: Zsh v: 5.9
  running-in: terminator inxi: 3.3.21
$cat /etc/host.conf
multi on
$cat /etc/hosts
(nothing)

Please ask me more infos if needed. I really need to use this laptop for work.

Any help will be appreciated.

Thank you.

It seems you have not updated in a while, this might also be the cause and issue you are experiencing since this kernel is EOL.

Have you tried rebooting the router you are connected to?
Can you boot to another kernel? 5.10 or 5.15?

Does removing the connection and recreating it again work?

NetworkManager can’t get a lease it seems so the other side might not be responding.

journalctl --boot | grep enp0s31f6 (the networkcard) might reveal some more info then just NetworkManager status and show what the system reports on the card.

So it is not the hardware.

Hello Hanzel,

Stange, i update regularly from the pamac gui. But it may concern only the applications, not the Kernel, i don’t know.

Oh, i have tried from many different networks (from different geo places) and even my phone as a wireless connection. Without success.

I have no idea how to do that. I can look for it though but now that i have no intenet connection, it is quite hard.

No. I have tried to “forget” a wifi network and re-enter credentials again or pull out the ethernet cable.

$journalctl --boot | grep enp0s31f6

oct. 13 22:25:19 thinkpad kernel: e1000e 0000:00:1f.6 enp0s31f6: renamed from eth0
oct. 13 22:25:37 thinkpad NetworkManager[871]: <info>  [1665692737.6592] manager: (enp0s31f6): new Ethernet device (/org/freedesktop/NetworkManager/Devices/2)
oct. 13 22:25:37 thinkpad NetworkManager[871]: <info>  [1665692737.6610] device (enp0s31f6): state change: unmanaged -> unavailable (reason 'managed', sys-iface-state: 'external')
oct. 13 22:25:45 thinkpad kernel: e1000e 0000:00:1f.6 enp0s31f6: NIC Link is Up 1000 Mbps Full Duplex, Flow Control: None
oct. 13 22:25:45 thinkpad kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp0s31f6: link becomes ready
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.6043] device (enp0s31f6): carrier: link connected
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.6058] device (enp0s31f6): state change: unavailable -> disconnected (reason 'carrier-changed', sys-iface-state: 'managed')
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.6105] device (enp0s31f6): Activation: starting connection 'Connexion filaire 1' (696d622f-0df1-3ced-92a7-719fc3fd4082)
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.6120] device (enp0s31f6): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.6132] device (enp0s31f6): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.6235] device (enp0s31f6): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.6251] dhcp4 (enp0s31f6): activation: beginning transaction (timeout in 45 seconds)
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.7281] dhcp4 (enp0s31f6): state changed new lease, address=192.168.1.118
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.7296] policy: set 'Connexion filaire 1' (enp0s31f6) as default for IPv4 routing and DNS
oct. 13 22:25:45 thinkpad NetworkManager[871]: <info>  [1665692745.9867] device (enp0s31f6): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'managed')
oct. 13 22:25:46 thinkpad NetworkManager[871]: <info>  [1665692746.1416] device (enp0s31f6): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'managed')
oct. 13 22:25:46 thinkpad NetworkManager[871]: <info>  [1665692746.1429] device (enp0s31f6): state change: secondaries -> activated (reason 'none', sys-iface-state: 'managed')
oct. 13 22:25:46 thinkpad NetworkManager[871]: <info>  [1665692746.1461] device (enp0s31f6): Activation: successful, device activated.
oct. 13 22:25:49 thinkpad NetworkManager[871]: <info>  [1665692749.0596] dhcp6 (enp0s31f6): activation: beginning transaction (timeout in 45 seconds)
oct. 13 22:25:49 thinkpad NetworkManager[871]: <info>  [1665692749.1466] dhcp6 (enp0s31f6): state changed new lease
oct. 13 22:25:53 thinkpad kernel: [UFW BLOCK] IN=enp0s31f6 OUT= MAC=01:00:5e:00:00:01:44:a6:1e:73:e7:f6:08:00 SRC=192.168.1.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0x80 TTL=1 ID=0 DF PROTO=2 
oct. 13 22:26:33 thinkpad kernel: [UFW BLOCK] IN=enp0s31f6 OUT= MAC=01:00:5e:00:00:01:44:a6:1e:73:e7:f6:08:00 SRC=192.168.1.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0x80 TTL=1 ID=0 DF PROTO=2 
oct. 13 22:27:13 thinkpad kernel: [UFW BLOCK] IN=enp0s31f6 OUT= MAC=01:00:5e:00:00:01:44:a6:1e:73:e7:f6:08:00 SRC=192.168.1.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0x80 TTL=1 ID=0 DF PROTO=2 
oct. 13 22:27:53 thinkpad kernel: [UFW BLOCK] IN=enp0s31f6 OUT= MAC=01:00:5e:00:00:01:44:a6:1e:73:e7:f6:08:00 SRC=192.168.1.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0x80 TTL=1 ID=0 DF PROTO=2 

I also desinstalled the protonVPN packageq from AUR via pamac. I used it with success for a while.

Any ideas ? It is chinese to me (if i may).

I’m not sure hot to read this this but could you disable the firewall?
Info on UWF:

when logged in run:

sudo mhwd-kernel --listinstalled
Will list the installed kernels. It is good practice to have 2 installed to check if something is kernel related.

When booting and holding down shift will present a boot menu and if there is more then 1 kernel installed the advanced options will have a item to start one of your choice. If this is not the case at the moment it is something to add to the todo list for later.

I’ve read your output the wrong way, the interface enp0s31f6 is the wired ethernet port.

Running journalctl --boot | grep wlp4s0 will show the log for the wireless interface.

Hello,
I disabled the firewall.

$sudo mhwd-kernel --listinstalled
e[32mCurrently running:e[0m 5.9.16-1-MANJARO (linux59)
The following kernels are installed in your system:
   * linux414
   * linux59

When booting, in the advanced options, i could boot on any of those kernels :

  • 5.9.16-1
  • 5.9.16-1 fallback initramfs
  • 4.14.280-1
  • 4.14.280-1 fallback initramfs

i tried the - 5.9.16-1 fallback initramfs and could not go on internet as well.

$ journalctl --boot | grep wlp4s0
oct. 14 23:40:31 thinkpad kernel: brcmfmac 0000:04:00.0 wlp4s0: renamed from wlan0
oct. 14 23:40:45 thinkpad NetworkManager[770]: <info>  [1665783645.4441] device (wlp4s0): driver supports Access Point (AP) mode
oct. 14 23:40:45 thinkpad NetworkManager[770]: <info>  [1665783645.4481] manager: (wlp4s0): new 802.11 Wi-Fi device (/org/freedesktop/NetworkManager/Devices/3)
oct. 14 23:40:45 thinkpad NetworkManager[770]: <info>  [1665783645.4498] device (wlp4s0): state change: unmanaged -> unavailable (reason 'managed', sys-iface-state: 'external')
oct. 14 23:40:46 thinkpad NetworkManager[770]: <info>  [1665783646.0187] device (wlp4s0): set-hw-addr: set MAC address to 1A:DD:5B:21:A3:DB (scanning)
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.0592] device (wlp4s0): supplicant interface state: internal-starting -> disconnected
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.0597] Wi-Fi P2P device controlled by interface wlp4s0 created
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.0611] manager: (p2p-dev-wlp4s0): new 802.11 Wi-Fi P2P device (/org/freedesktop/NetworkManager/Devices/5)
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.0622] device (p2p-dev-wlp4s0): state change: unmanaged -> unavailable (reason 'managed', sys-iface-state: 'external')
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.0644] device (wlp4s0): state change: unavailable -> disconnected (reason 'supplicant-available', sys-iface-state: 'managed')
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.0665] device (p2p-dev-wlp4s0): state change: unavailable -> disconnected (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.5720] device (wlp4s0): Activation: starting connection 'cequejevois-wifi' (2b3cf1c2-1262-44fa-8997-06f1cffeb10b)
oct. 14 23:40:47 thinkpad NetworkManager[770]: <info>  [1665783647.5724] device (wlp4s0): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.0991] device (wlp4s0): set-hw-addr: reset MAC address to C8:FF:28:FF:EC:04 (preserve)
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.1022] device (wlp4s0): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.1032] device (wlp4s0): Activation: (wifi) access point 'cequejevois-wifi' has security, but secrets are required.
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.1033] device (wlp4s0): state change: config -> need-auth (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.1040] sup-iface[153351fde9173f53,0,wlp4s0]: wps: type pbc start...
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.1076] device (wlp4s0): state change: need-auth -> prepare (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.1092] device (wlp4s0): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.1102] device (wlp4s0): Activation: (wifi) connection 'cequejevois-wifi' has security, and secrets exist.  No new secrets needed.
oct. 14 23:40:48 thinkpad wpa_supplicant[1002]: wlp4s0: WPS-CANCEL
oct. 14 23:40:48 thinkpad wpa_supplicant[1002]: wlp4s0: Trying to associate with SSID 'cequejevois-wifi'
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.2267] device (wlp4s0): supplicant interface state: disconnected -> associating
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.2268] device (p2p-dev-wlp4s0): supplicant management interface state: disconnected -> associating
oct. 14 23:40:48 thinkpad wpa_supplicant[1002]: wlp4s0: Associated with 44:a6:1e:73:e7:f6
oct. 14 23:40:48 thinkpad wpa_supplicant[1002]: wlp4s0: CTRL-EVENT-SUBNET-STATUS-UPDATE status=0
oct. 14 23:40:48 thinkpad wpa_supplicant[1002]: wlp4s0: CTRL-EVENT-REGDOM-CHANGE init=COUNTRY_IE type=COUNTRY alpha2=FR
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.7865] device (wlp4s0): supplicant interface state: associating -> 4way_handshake
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.7867] device (p2p-dev-wlp4s0): supplicant management interface state: associating -> 4way_handshake
oct. 14 23:40:48 thinkpad wpa_supplicant[1002]: wlp4s0: WPA: Key negotiation completed with 44:a6:1e:73:e7:f6 [PTK=CCMP GTK=CCMP]
oct. 14 23:40:48 thinkpad kernel: IPv6: ADDRCONF(NETDEV_CHANGE): wlp4s0: link becomes ready
oct. 14 23:40:48 thinkpad wpa_supplicant[1002]: wlp4s0: CTRL-EVENT-CONNECTED - Connection to 44:a6:1e:73:e7:f6 completed [id=0 id_str=]
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8004] device (wlp4s0): supplicant interface state: 4way_handshake -> completed
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8006] device (wlp4s0): Activation: (wifi) Stage 2 of 5 (Device Configure) successful. Connected to wireless network "cequejevois-wifi"
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8006] device (p2p-dev-wlp4s0): supplicant management interface state: 4way_handshake -> completed
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8012] device (wlp4s0): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8032] dhcp4 (wlp4s0): activation: beginning transaction (timeout in 45 seconds)
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8300] dhcp4 (wlp4s0): state changed new lease, address=192.168.1.29
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8315] policy: set 'cequejevois-wifi' (wlp4s0) as default for IPv4 routing and DNS
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8606] device (wlp4s0): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8662] device (wlp4s0): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8668] device (wlp4s0): state change: secondaries -> activated (reason 'none', sys-iface-state: 'managed')
oct. 14 23:40:48 thinkpad NetworkManager[770]: <info>  [1665783648.8711] device (wlp4s0): Activation: successful, device activated.
oct. 14 23:40:50 thinkpad NetworkManager[770]: <info>  [1665783650.1073] dhcp6 (wlp4s0): activation: beginning transaction (timeout in 45 seconds)
oct. 14 23:40:50 thinkpad NetworkManager[770]: <info>  [1665783650.4166] dhcp6 (wlp4s0): state changed new lease

I’ve tried both wifi and ethernet connections on my previous tests anyway.

Do you really think it is a question of kernel ? And not a misconfiguration of some resolv.conf files somewhere.

$cat /etc/resolv.conf
nameserver ::1

In the network manager interface, when accessing my network wifi (cequejevois-wifi), i used to add two manual DNS in the ipv4 section. But i disabled them to return to automatic and made tests with (as usual) and without them. I am using automatic DHCP.

Don’t know if it may help or not.

I’m not sure what is going on on your system, it seems to recognize the hardware alright and make the
connection. Why DNS does not work, I have no Idea.

Does dns resolving work with the manually added dns servers?

Does NetworkManager update the resolv.conf file?
Check with stat /etc/resolv.conf

If you dual boot with windows, disable fastboot.

All the kernels on the system are not supported anymore, try to get your system updated with the connection on the fixed ethernet port if wifi keeps giving trouble. Update the mirrors when a stable connection is made:

Edit: There is somebody with a similair looking problem.

vs:

You only have an IPv6 nameserver
(which is probably also not correct, but I do know next to nothing about IPv6)
but somehow get and use IPv4 addresses otherwise.

I’d disable IPv6 in NetworkManager GUI and - if you set DNS servers manually - make sure that the method to get an address is set to:
“Automatic (DHCP), Addresses only”

the content of your /etc/resolv.conf does not seem to match reality

and:

that file should not be empty


cat /etc/resolv.conf
nameserver ::1

nameserver ::1 is, as far as I can see, the IPv6 loopback address - it is not a valid nameserver

Hello,
The very similar looking problem found by @Hanzel (wich is indeed very similar to what is hapening to me) helped me to connect to internet. I followed the same logic and, by manually adding nameserver 192.168.1.1 to my resolv.conf file i could connect to internet.

Once online, i upgraded the kernel and all the other applications. So now i am on 5.15.72-1-MANJARO linux kernel.

It seems that Network Manager is regularly, or each time i change network (from wifi to ethernet and vice versa) or changing anything in Network Manager GUI, changing the resolv.conf file automatically to this one line nameserver ::1, which is indeed IPV6.

  • i disabled IPV6 in each networks (wifi and ethernet)
  • everything is in automatic DHCP, automatic routes, without the manual DNS that i used to add
  • these manual DNS worked before i posted in the forum, now i am not using them (nor in gui nor in resolv.conf) to keep things simple
  • i have no dual boot, only manjaro, but /home is luks encrypted
  • my resolver issues were both on ethernet or wifi network

More info :

$stat /etc/resolv.conf
Fichier : /etc/resolv.conf
   Taille : 68        	Blocs : 8          Blocs d'E/S : 4096   fichier
Périphérique : 254/0	Inœud : 4327236     Liens : 1
Accès : (0644/-rw-r--r--)  UID : (    0/    root)   GID : (    0/    root)
 Accès : 2022-10-15 23:33:38.290016988 +0200
Modif. : 2022-10-15 23:33:38.290016988 +0200
Changt : 2022-10-15 23:33:38.290016988 +0200
  Créé : 2022-10-15 23:33:38.290016988 +0200

Yes, in my opinion, NM updates the file.

$nmcli dev show | grep DNS
IP4.DNS[1]:                             192.168.1.1
IP6.DNS[1]:                             ::1

I don’t know why and how Network Manager change the resolv.conf file (same question as in the stackexchange post, without answer yet), and i have to manually insert 192.168.1.1 each time. But it is better than before.

Now digging into resolv.conf and hosts man pages.

Thank you.

1 Like

Can you try checking for NetworkManager errors while doing the change? In a terminal enter

journalctl -f

Then while following, make a network change, example disconnect and reconnect. When finished with it, Ctrl-C to end the follow.

Hi all,

Somebody that i physically met today helped me with these things and now everything is fine.

For what i have understood, ProtonVPN, that i installed then uninstalled last week, still made troubles.

The issue is better explained here below.

https://askubuntu.com/questions/1428252/cant-remove-pvpn-ipv6leak-protection-connection-after-protonvpn-complete-removi

#nmcli dev delete ipv6leakintr0

was not enough and he had to

#rm system-connections/pvpn-ipv6leakintr0

Since ProtonVPN was uninstalled, it was very hard to find that it came from it and he had to use commands like :

#vim /etc/systemd/resolved.conf
#netstat -nlp
#systemctl status systemd-resolved.service
#systemctl stop systemd-resolved
#ip a

to do the tricks. It was far beyond my knowledge. Please consider that these commands are given here by memory and may not be accurate. But you have the idea and it may be usefull for others.

Thank you for your help anyway.

1 Like

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