# Connman

Related articles

- Network configuration
- Wireless network configuration
- Category:Network managers

ConnMan is an alternative to NetworkManager and Wicd and was created by Intel and the Moblin project for use with embedded devices. ConnMan is designed to be light on resources making it ideal for netbooks, and other mobile devices. It is modular in design takes advandage of the dbus API and provides proper abstraction on top of wpa_supplicant. ConnMan currently has plugins available for:

- Wi-Fi
- Ethernet
- Bluetooth (Through bluez)
- WiMAX
- VPN's (Through the `connman-vpn.service`)

It is typically used for wireless networking and is extremely fast at resolving connections. After setup you may wish to check for yourself with `systemd-analyze blame` to see the difference in performance compared to other network managers.

## Installation

Install connman from the official repositories. wpa_supplicant is an optional dependency needed for Wi-Fi functionality.

Start and enable `connman.service`. If present, stop and disable other networking services to prevent conflicts (e.g `netctl.service`).

### Desktop clients

ConnMan only has three working panel applets, a dmenu client and a simple notification client:

- cmst — Qt GUI for ConnMan.

  https://github.com/andrew-bibb/cmst || cmst

- EConnman — Enlightenment desktop panel applet.

  http://www.enlightenment.org || econnman

- ConnMan-UI — GTK+ client applet.

  https://github.com/tbursztyka/connman-ui || connman-ui-git

- connman_dmenu — Client/frontend for dmenu.

  https://github.com/taylorchu/connman_dmenu || connman_dmenu-git

- connman-notify — Connman event notification client

  https://github.com/wavexx/connman-notify || not packaged? search in AUR

Currently the GTK client is not 100% stable, however it is good enough for day-to-day usage. To use it just add `connman-ui-gtk` to one of your startup files, e.g: `autostart` for Openbox.

## Usage

ConnMan has a standard command line client `connmanctl`. It can run in 2 modes:

- In command mode commands are entered as arguments to `connmanctl` command, just like `systemctl`.
- Interactive mode is started by typing `connmanctl` without arguments. Prompt will change to `connmanctl>` to indicate it is waiting for user commands, just like python interactive mode.

### Wired

ConnMan will automatically handle wired connections.

### Wi-Fi

Note: Make sure the Wi-Fi device is listed in the output of `ip link show up`. If it is not listed that means it is not powered on. Use `Fn` keys on the laptop to turn it on.

#### Connecting to an open access point

The commands in this section show how to run `connmanctl` in command mode.

To scan the network `connmanctl` accepts simple names called technologies. To scan for nearby Wi-Fi networks:

    $ connmanctl scan wifi

To list the available networks found after a scan run (example output):

    $ connmanctl services

    *AO MyNetwork               wifi_dc85de828967_68756773616d_managed_psk
        OtherNET                wifi_dc85de828967_38303944616e69656c73_managed_psk
        AnotherOne              wifi_dc85de828967_3257495245363836_managed_wep
        FourthNetwork           wifi_dc85de828967_4d7572706879_managed_wep
        AnOpenNetwork           wifi_dc85de828967_4d6568657272696e_managed_none

To connect to an open network simple use the enter the second field beginning with wifi_:

    $ connmanctl connect wifi_dc85de828967_4d6568657272696e_managed_none

You should now be connected to the network. Check using `ip addr` or `connmanctl state`.

#### Connecting to a protected access point

For protected access points you will need to provide some information to the ConnMan daemon, at the very least a password or a passphrase.

The commands in this section show how to run `connmanctl` in interactive mode, it is required for running the `agent` command. To start interactive mode simply type:

    $ connmanctl

You then proceed almost as above, first scan for any Wi-Fi technologies:

    connmanctl> scan wifi

To list services:

    connmanctl> services

Now you need to register the agent to handle user requests. The command is:

    connmanctl> agent on

You now need to connect to one of the protected services. To do this it is very handy to have a terminal that allows cut and paste. If you were connecting to OtherNET in the example above you would type:

    connmanctl> connect wifi_dc85de828967_38303944616e69656c73_managed_psk

The agent will then ask you to provide any information the daemon needs to complete the connection. The information requested will vary depending on the type of network you are connecting to. The agent will also print additional data about the information it needs as shown in the example below.

    Agent RequestInput wifi_dc85de828967_38303944616e69656c73_managed_psk
      Passphrase = [ Type=psk, Requirement=mandatory ]
      Passphrase?

Provide the information requested, in this example the passphrase, and then type:

    connmanctl> quit

If the information you provided is correct you should now be connected to the protected access point.

### Settings

Settings and profiles are automatically created for networks the user connects to often. They contain feilds for the passphrase, essid and other information. Profile settings are stored in directories under `/var/lib/connman/` by their service name. To view all network profiles run this command from root shell:

    # cat /var/lib/connman/*/settings

Note: VPN settings can be found in `/var/lib/connman-vpn/`

### Technologies

Various hardware interfaces are referred to as Technologies by ConnMan.

To list available technologies run:

    $ connmanctl technologies

To get just the types by their name one can use this one liner:

    $ connmanctl technologies | awk '/Type/ { print $NF }'

Note: The field `Type = tech_name` provides the technology type used with `connmanctl` commands

To interact with them one must refer to the technology by type. Technologies can be toggled on/off with:

    $ connmanctl enable technology_type

and:

    $ connmanctl disable technology_type

For example to toggle off wifi:

    $ connmanctl disable wifi

## Automatic switching between wired and wireless

ConnMan supports automatic switching of saved profiles with `PreferredTechnologies` option. This works great, but can leave you with both wireless and wired enabled at the same time. To circumvent this you need to enable the `SingleConnectedTechnology` option. The result of the new configuration file you need to add at `/etc/connman/main.conf` is:

    [General]
    PreferredTechnologies=ethernet,wifi
    SingleConnectedTechnology=true

And make sure to restart the `connman.service`.

For testing purposes it is recommended to watch the journal and plug the network cable a few times to see the action.

## See also

For further detailed information on ConnMan refer to this documentation: http://git.kernel.org/cgit/network/connman/connman.git/plain/doc/overview-api.txt?id=HEAD

Category:

- Network managers