Using InterMux

01 Before you start

InterMux runs on Linux with systemd and network namespaces. Run it as your normal user, never with sudo. Network changes go through a small polkit-gated helper, so a password prompt appears when root work is needed.

If it is not installed yet, the one-line installer sets it up and checks the dependencies:

curl -fsSL https://intermux.me/install.sh | sh

Then see what is available on the machine:

intermux check
intermux interfaces
intermux apps --search firefox

check reports missing tools. interfaces lists the connections you can bind, and apps searches the installed desktop applications. Flatpak apps cannot be bound because they run in their own sandbox.

02 Your first binding

A binding is one interface plus one application. Use bind to start the app inside a namespace routed through that interface:

intermux bind --app firefox --iface wlan0

The app starts as you, with your profile and settings. Everything it sends leaves through wlan0. When the last process of the app exits, a background watcher removes the binding.

DNS can be a preset or a comma-separated list of addresses:

intermux bind --app firefox --iface wlan0 --dns quad9
intermux bind --app qbittorrent --iface eth0 --dns 1.1.1.1,9.9.9.9

Presets are auto, cloudflare, google and quad9. If the app is already running, add --separate-profile to open a second copy, or --close-existing to close and reopen it.

03 Check what is running

intermux status

status shows every binding and every routed running app. For each namespace it also reports the DNS servers, the bandwidth limit and the traffic counters. To confirm which address the outside world sees:

intermux verify --iface wlan0

04 Everyday commands

intermux move --app firefox \
  --iface wlan0 --to wg0

intermux restart --app firefox --iface wlan0

intermux dns --iface wlan0 1.1.1.1,9.9.9.9

intermux limit --iface wlan0 \
  --down 20 --up 5

Running apps pick up DNS changes without a restart. A bandwidth limit covers every app on that interface together; run limit without values to remove it. Moving an app restarts it, because routing belongs to the namespace.

Use stop for one binding and kill for every host instance of an app. reconnect re-adds routes after a link comes back.

intermux stop --app firefox --iface wlan0
intermux kill --app firefox
intermux reconnect

05 Apps that are already open

adopt routes a running app through an interface without closing it. InterMux moves its processes into a cgroup and marks its packets, so new connections use the chosen link:

intermux adopt --app firefox --iface eth0

The command prints an ID. Give that ID to release to stop routing the app:

intermux release <ID>

Connections the app already had open keep their old route until they reconnect. Name lookups for an adopted app use the normal system route, not the chosen interface, and IPv6 for the adopted group is rejected so traffic cannot leak around the interface. This needs cgroup v2 and nft.

06 Command reference

Run intermux <command> --help for flags and details. helper and watch are internal and are not meant to be run directly.

07 The window

Run intermux with no command to open the GUI, or start it from your application menu. Do not run it as root. The window has three sections: New binding, Queue and Bindings.

If an app is already running when its queue starts, InterMux asks what to do: close and reopen it, open a separate profile, Shift current session to move the running copy without restarting it, or cancel. VPN connections… connects or imports NetworkManager VPNs. Refresh, Re-add routes, Remove stopped and Reset everything are in the same toolbar.

08 Clean up and undo

Bindings normally disappear when their apps exit. To tidy up the rest, or to start over:

intermux teardown-idle
intermux reset --kill-apps --yes

reset removes everything InterMux created. Add --kill-apps to also stop the applications it started, and --yes to skip the confirmation. To remove the program itself:

curl -fsSL https://intermux.me/install.sh | sh -s -- --uninstall

09 Troubleshooting

Each binding writes a log under ~/.local/state/intermux/logs. In the GUI, Open log opens the selected app's log. For verbose output on stderr:

INTERMUX_DEBUG=1 intermux status

intermux report writes a zip of diagnostics to ~/intermux-reports (change the folder with --out DIR). Nothing is uploaded automatically. If idle bindings are not cleaned up, check the watcher:

sudo systemctl status intermux-watch.service
sudo systemctl enable --now intermux-watch.service

InterMux is beta software that changes system networking. Try it first on a machine you can recover from a mistake.