DNS Switcher for Ubuntu Desktop

Small GUI app for switching the active NetworkManager connection between editable DNS profiles.

Default profiles:

• Restricted / local AdGuard DNS: 192.168.1.2
• More open / Quad9 DNS: 9.9.9.9
• Automatic DNS from DHCP/router

The app uses nmcli through pkexec. It does not edit /etc/resolv.conf directly.

Install

sudo apt update
sudo apt install python3 python3-tk network-manager
./install.sh

Then open DNS Switcher from the app menu, or run:

dns-switcher

Managing DNS profiles

Open Profiles → Manage DNS profiles… or press Manage… next to the DNS profile selector.

You can:

• add a new DNS profile
• edit an existing DNS profile
• delete profiles
• reset back to the defaults

Profiles are saved here:

~/.config/dns-switcher/profiles.json

DNS IPs can be entered as a space-separated or comma-separated list, for example:

192.168.1.2
9.9.9.9, 149.112.112.112

IPv4 and IPv6 addresses are validated before saving.

What it changes

For the selected active connection, a manual DNS profile sets:

ipv4.dns "<selected IPv4 DNS list>"
ipv4.ignore-auto-dns yes
ipv6.dns "<selected IPv6 DNS list>"
ipv6.ignore-auto-dns yes

The automatic DNS ignore flags are intentional: otherwise a router-provided DNS server can bypass the selected manual DNS profile.

Automatic mode clears manual DNS and re-enables automatic DNS:

ipv4.dns ""
ipv4.ignore-auto-dns no
ipv6.dns ""
ipv6.ignore-auto-dns no

Troubleshooting

Check active DNS:

resolvectl dns
resolvectl status

Check the NetworkManager connection profile:

nmcli connection show
nmcli connection show "YOUR_CONNECTION_NAME"

If your system does not use NetworkManager for the active connection, this app is the wrong abstraction. Use Netplan/systemd-networkd instead.