DNS are not removed after disconnecting the vpn?

Issues & Assistance Networking Support
1

Hello.

Post your terminal/konsole in- and output as text (no pictures) from:

System:
  Kernel: 5.16.0-zen1-1-zen x86_64 bits: 64 compiler: gcc v: 11.1.0
    parameters: BOOT_IMAGE=/@/boot/vmlinuz-linux-zen
    root=UUID=6b13a369-b041-4975-8b36-e67239723d2c rw rootflags=subvol=@
    quiet splash rd.udev.log_priority=3 vt.global_cursor_default=0 loglevel=3
  Desktop: i3 4.20.1 info: i3bar vt: 7 dm: LightDM 1.30.0
    Distro: Garuda Linux base: Arch Linux
Machine:
  Type: Laptop System: Acer product: Nitro AN515-54 v: V1.33
    serial: <superuser required>
  Mobo: CFL model: Octavia_CFS v: V1.33 serial: <superuser required>
    UEFI: Insyde v: 1.33 date: 11/17/2020
Battery:
  ID-1: BAT1 charge: 39.0 Wh (94.7%) condition: 41.2/58.8 Wh (70.2%)
    volts: 16.6 min: 15.4 model: SMP AP18E7M type: Li-ion serial: <filter>
    status: Charging
CPU:
  Info: model: Intel Core i7-9750H bits: 64 type: MT MCP arch: Coffee Lake
    family: 6 model-id: 0x9E (158) stepping: 0xA (10) microcode: 0xEA
  Topology: cpus: 1x cores: 6 tpc: 2 threads: 12 smt: enabled cache:
    L1: 384 KiB desc: d-6x32 KiB; i-6x32 KiB L2: 1.5 MiB desc: 6x256 KiB
    L3: 12 MiB desc: 1x12 MiB
  Speed (MHz): avg: 1051 high: 3818 min/max: 800/4500 scaling:
    driver: intel_pstate governor: powersave cores: 1: 3818 2: 800 3: 800
    4: 800 5: 800 6: 800 7: 800 8: 800 9: 800 10: 800 11: 800 12: 800
    bogomips: 62399
  Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx
  Vulnerabilities:
  Type: itlb_multihit status: KVM: VMX disabled
  Type: l1tf
    mitigation: PTE Inversion; VMX: conditional cache flushes, SMT vulnerable
  Type: mds mitigation: Clear CPU buffers; SMT vulnerable
  Type: meltdown mitigation: PTI
  Type: spec_store_bypass
    mitigation: Speculative Store Bypass disabled via prctl
  Type: spectre_v1
    mitigation: usercopy/swapgs barriers and __user pointer sanitization
  Type: spectre_v2 mitigation: Full generic retpoline, IBPB: conditional,
    IBRS_FW, STIBP: conditional, RSB filling
  Type: srbds mitigation: Microcode
  Type: tsx_async_abort status: Not affected
Graphics:
  Device-1: Intel CoffeeLake-H GT2 [UHD Graphics 630]
    vendor: Acer Incorporated ALI driver: i915 v: kernel bus-ID: 00:02.0
    chip-ID: 8086:3e9b class-ID: 0300
  Device-2: NVIDIA TU117M [GeForce GTX 1650 Mobile / Max-Q]
    vendor: Acer Incorporated ALI driver: nvidia v: 495.46
    alternate: nouveau,nvidia_drm bus-ID: 01:00.0 chip-ID: 10de:1f91
    class-ID: 0300
  Device-3: Quanta HD Webcam type: USB driver: uvcvideo bus-ID: 1-5:3
    chip-ID: 0408:a060 class-ID: 0e02 serial: <filter>
  Display: x11 server: X.Org 1.21.1.3 driver: loaded: modesetting,nvidia
    display-ID: :0 screens: 1
  Screen-1: 0 s-res: 1920x1848 s-dpi: 97 s-size: 504x485mm (19.8x19.1")
    s-diag: 699mm (27.5")
  Monitor-1: eDP-1 res: 1920x1080 hz: 60 dpi: 142
    size: 344x193mm (13.5x7.6") diag: 394mm (15.5")
  Monitor-2: HDMI-1-0 res: 1366x768 hz: 60 dpi: 85
    size: 410x230mm (16.1x9.1") diag: 470mm (18.5")
  Message: Unable to show advanced data. Required tool glxinfo missing.
Audio:
  Device-1: Intel Cannon Lake PCH cAVS vendor: Acer Incorporated ALI
    driver: snd_hda_intel v: kernel
    alternate: snd_soc_skl,snd_sof_pci_intel_cnl bus-ID: 00:1f.3
    chip-ID: 8086:a348 class-ID: 0403
  Device-2: NVIDIA vendor: Acer Incorporated ALI driver: snd_hda_intel
    v: kernel bus-ID: 01:00.1 chip-ID: 10de:10fa class-ID: 0403
  Sound Server-1: ALSA v: k5.16.0-zen1-1-zen running: yes
  Sound Server-2: JACK v: 1.9.20 running: no
  Sound Server-3: PulseAudio v: 15.0 running: no
  Sound Server-4: PipeWire v: 0.3.43 running: yes
Network:
  Device-1: Intel Cannon Lake PCH CNVi WiFi driver: iwlwifi v: kernel
    bus-ID: 00:14.3 chip-ID: 8086:a370 class-ID: 0280
  IF: wlp0s20f3 state: up mac: <filter>
  Device-2: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
    vendor: Acer Incorporated ALI driver: r8169 v: kernel port: 3000
    bus-ID: 06:00.0 chip-ID: 10ec:8168 class-ID: 0200
  IF: enp6s0 state: down mac: <filter>
  IF-ID-1: br-d4230d5827ef state: down mac: <filter>
  IF-ID-2: docker0 state: down mac: <filter>
Bluetooth:
  Device-1: Intel Bluetooth 9460/9560 Jefferson Peak (JfP) type: USB
    driver: btusb v: 0.8 bus-ID: 1-14:4 chip-ID: 8087:0aaa class-ID: e001
  Report: bt-adapter ID: hci0 rfk-id: 1 state: down
    bt-service: enabled,running rfk-block: hardware: no software: no
    address: <filter>
RAID:
  Hardware-1: Intel 82801 Mobile SATA Controller [RAID mode] driver: ahci
    v: 3.0 port: 5060 bus-ID: 00:17.0 chip-ID: 8086:282a rev: N/A
    class-ID: 0104
Drives:
  Local Storage: total: 931.51 GiB used: 43.74 GiB (4.7%)
  SMART Message: Required tool smartctl not installed. Check --recommends
  ID-1: /dev/sda maj-min: 8:0 vendor: Crucial model: CT1000MX500SSD4
    size: 931.51 GiB block-size: physical: 4096 B logical: 512 B
    speed: 6.0 Gb/s type: SSD serial: <filter> rev: 023 scheme: GPT
Partition:
  ID-1: / raw-size: 442.94 GiB size: 442.94 GiB (100.00%)
    used: 15.15 GiB (3.4%) fs: btrfs dev: /dev/sda2 maj-min: 8:2
  ID-2: /boot/efi raw-size: 301 MiB size: 300.4 MiB (99.79%)
    used: 576 KiB (0.2%) fs: vfat dev: /dev/sda1 maj-min: 8:1
  ID-3: /home raw-size: 442.94 GiB size: 442.94 GiB (100.00%)
    used: 15.15 GiB (3.4%) fs: btrfs dev: /dev/sda2 maj-min: 8:2
  ID-4: /var/log raw-size: 442.94 GiB size: 442.94 GiB (100.00%)
    used: 15.15 GiB (3.4%) fs: btrfs dev: /dev/sda2 maj-min: 8:2
  ID-5: /var/tmp raw-size: 442.94 GiB size: 442.94 GiB (100.00%)
    used: 15.15 GiB (3.4%) fs: btrfs dev: /dev/sda2 maj-min: 8:2
Swap:
  Kernel: swappiness: 133 (default 60) cache-pressure: 100 (default)
  ID-1: swap-1 type: zram size: 31.19 GiB used: 0 KiB (0.0%) priority: 100
    dev: /dev/zram0
Sensors:
  System Temperatures: cpu: 51.0 C pch: 62.0 C mobo: N/A
  Fan Speeds (RPM): N/A
Info:
  Processes: 327 Uptime: 3h 17m wakeups: 1 Memory: 31.19 GiB
  used: 3.8 GiB (12.2%) Init: systemd v: 250 tool: systemctl Compilers:
  gcc: 11.1.0 clang: 13.0.0 Packages: pacman: 1257 lib: 314 Shell: Zsh v: 5.8
  running-in: alacritty inxi: 3.3.11

I am facing strange issue with l2tp/ipsec-psk vpn. I installed networkmanager-l2tp and added connection from the UI. VPN connects, works well.
But VPN dns are not flushed when I disconnect VPN. I have to reconnect wifi everytime after vpn disconnect to get back the router dns.

A quick search shows an issue dating back to 2018 in network manager persisting the dns but that's too old. I am not sure whether that is the reason and the bug seems to be fixed.

2
3 Likes
3

I tested on other Windows PC, it seems to be working. Asked my co-worker using debian if he’s having any problem, none.

4

Doesn’t Debian use kernels and software from the Precambrian era?

Again, isn’t that kind of Apples to Oranges?

Oh wait, you forgot to include an Apple computer comparison, my bad.

2 Likes
5

That was not a comparison, I was simply stating my findings to the question whether it’s upstream vpn problem. LOL!

6

So what actions do you need to take to get a connection afterwards?

7

Either restart the interface or edit /etc/resolv manually and removing the private dns ips

8

I meant restart the interface, by what method? Will a simple restart with the network manger applet suffice, or do you need to lower and raise your adapter via the terminal? Just trying to get an idea of the inconvenience factor here.

9

Just restarting the NetworkManager (systemctl restart NetworkManager) resets the dns back to normal. Or I can just disconnect and connect from the GUI too.

1 Like
10

Definitely an annoyance, but certainly only a minor inconvenience, (if it can be fixed with a simple click on the NM applet).

Good luck finding a resolution, but I'm certainly not going to waste any of my time time looking for a fix for a bug this minor in nature.

2 Likes