Difference between revisions of "ConnMan"

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m (→‎Installation: Added LXQT-Connman-Applet, as well as arranged the programs in alphabetical order, as it seemed to be just random order.)
m (Added note on disabling dhcpcd, since connman provides the functionality.)
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[[systemd#Using units|Start and enable]] {{ic|connman.service}}.
[[systemd#Using units|Start and enable]] {{ic|connman.service}}.
If present, stop and disable other [[:Category:Network_managers|networking services]] to prevent conflicts (e.g {{ic|netctl.service}}).
If present, stop and disable other [[:Category:Network_managers|networking services]] to prevent conflicts (e.g {{ic|netctl.service}}). Note that even [[dhcpcd]] can be disabled, since connman provides the relevant functionality.
=== Desktop clients ===
=== Desktop clients ===

Revision as of 15:40, 25 April 2015

ConnMan is a command-line network manager designed for use with embedded devices. ConnMan is light on resources, making it ideal for netbooks and other mobile devices. It is modular through its use of a plugin system, as opposed to having all functionality built in. Plugins are currently available for:

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

It is extremely fast at resolving connections as well as in its startup time. After the initial setup, you may wish to check for yourself with systemd-analyze blame to see the difference in startup time compared to other network managers.


Install the connman package from the official repositories. wpa_supplicant and bluez are optional dependencies required for Wi-Fi and Bluetooth functionality respectively.

Start and enable connman.service. If present, stop and disable other networking services to prevent conflicts (e.g netctl.service). Note that even dhcpcd can be disabled, since connman provides the relevant functionality.

Desktop clients

  • cmst — Qt GUI for ConnMan.
https://github.com/andrew-bibb/cmst || cmstAUR
  • connman-ncurses — Simple ncurses UI for ConnMan
https://github.com/eurogiciel-oss/connman-json-client || connman-ncurses-gitAUR
  • connman-notify — Connman event notification client
https://github.com/wavexx/connman-notify || connman-notifyAUR
  • ConnMan-UI — GTK3 client applet.
https://github.com/tbursztyka/connman-ui || connman-ui-gitAUR
  • connman_dmenu — Client/frontend for dmenu.
https://github.com/taylorchu/connman_dmenu || connman_dmenu-gitAUR
  • EConnman — Enlightenment desktop panel applet.
http://www.enlightenment.org || econnmanAUR
  • LXQT-Connman-Applet — LXQT desktop panel applet.
https://github.com/surlykke/lxqt-connman-applet || lxqt-connman-applet-gitAUR
  • qconnman-ui — Qt management interface used on O.S. Systems products
https://github.com/OSSystems/qconnman-ui || qconnman-ui-gitAUR

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.

connman-ncurses: not all of connman functionality is implemented; but usable (with X or from terminal without X). See wiki.


Tango-view-fullscreen.pngThis article or section needs expansion.Tango-view-fullscreen.png

Reason: Only Wired and Wi-Fi plugins are described. (Discuss in Talk:ConnMan#)

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.


ConnMan will automatically handle wired connections.


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. You may need to run connmanctl enable wifi.

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, use 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 ]

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 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/.


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


$ connmanctl disable technology_type

For example to toggle off wifi:

$ connmanctl disable wifi
Warning: connman grabs all rfkill events. It is most likely impossible to use rfkill or bluetoothctl to (un)block devices. Always use connmanctl enable|disable

Tips and tricks

Avoid changing the hostname

By default, ConnMan changes the transient hostname on a per network basis. This can create problems with X authority: If ConnMan changes your hostname to something else than the one used to generate the xauth magic cookie, then it will become impossible to create new windows. Symptoms are error messages like "No protocol specified" and "Can't open display: :0.0". Manually resetting the host name fixes this, but a permanent solution is to prevent ConnMan from changing your host name in the first place. This can be accomplished by adding the following to /etc/connman/main.conf:


Make sure to restart the connman.service after changing this file.

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

Prefer ethernet to wireless

By default ConnMan does not prefer ethernet over wireless, which can lead to it deciding to stick with a slow wireless network even when ethernet is available. You can tell connman to prefer ethernet adding the following to /etc/connman/main.conf:


Exclusive connection

ConnMan allows you to be connected to both ethernet and wireless at the same time. This can be useful as it allows programs that established a connection over wifi to stay connected even after you connect to ethernet. But some peope prefer to have only a single unambiguous connection active at a time. That behavior can be activated by adding the following to /etc/connman/main.conf:


Connecting to eduroam

See WPA2_Enterprise#connman.

Avoiding conflicts with local DNS server

If you are running a local DNS server, it will likely have problems binding to port 53 (TCP and/or UDP) after installing Connman. This is because Connman includes its own DNS proxy which also tries to bind to those ports. If you see log messages from BIND or dnsmasq like "named[529]: could not listen on UDP socket: address in use", this could be the problem. (Verify connmand is listening on that port with netstat -tulpn.)

To fix this connmand can be started with the -r or --nodnsproxy by overriding the systemd service file. Create the folder /etc/systemd/system/connman.service.d/ and add the file disable_dns_proxy.conf:

ExecStart=/usr/bin/connmand -n --nodnsproxy

Make sure to reload the systemd daemon and restart the connman.service, and your DNS proxy, after adding this file.

Blacklist interfaces

If something like Docker is creating virtual interfaces Connman may attempt to connect to one of these instead of your physical adapter if the connection drops. A simple way of avoiding this is to blacklist the interfaces you do not want to use. Connman will by default blacklist interfaces starting with "vmnet", "vboxnet", "virbr" and "ifb" so those need to be included as well. If it does not already exist, create /etc/connman/main.conf:


Once connman.service has been restarted this will also hide all the "veth#######" interfaces from GUI tools like Econnman.

See also

For further detailed information on ConnMan you may refer to the documentation in its git repo at [1].