BT DUN device disappears permanently from nm-applet if connection broken

[Steve White]

Hi,

I'm a daily Bluetooth DUN user. This is Ubuntu 12.04, on a Samsung NC-20 with a Nokia C5.

I can easily establish a DUN connection through the phone and comfortably use the Internet that way.
After set-up, an item corresponding to my phone provider appears in the Gnome NetworkManager (nm-applet) menu.

However, if the DUN connection is broken, say by turning the phone off, or taking the phone out of range,
the item disappears from the menu, and never comes back, even if the phone is in range and Bluetooth is clearly working on both devices.

This is 100% reproducible on my system.
This is an old problem: I remember it from the Ubuntu 10.x series.

I tried re-starting nm-applet, and bluetooth-applet, to no effect.
If the bluetoothd is restarted, however, the item re-appears, and the phone can again be used.
(Re-booting the computer works too of course.)

I'm guessing it's a bluez issue, although it might be a NetworkManager issue (or both).

Cheers!

[Mathieu Trudel-Lapierre (cyphermox)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Unfortunately we can't start working on it yet, because your bug report didn't include enough information.

Please include the information requested at https://wiki.ubuntu.com/DebuggingNetworkManager. If you have trouble, do not hesitate to ask for more assistance. Thanks in advance.

[Steve White (stevan-white)]

Hi Mathieu,

I will do ask you ask.

But have you tried this yourself? It's very easy, and it causes the problem every time (happened again this afternoon, in fact).

[Steve White (stevan-white)]

I ran the script you asked for, and attach the results.

See *at least* two different kinds of failures of Bluetooth network connections.

One seems to be associated with network activity, particularly with Skype.
(Although, I have conducted long Skype sessions through the same interface.)
This of course shouldn't happen at all.

The other happens when the cell phone goes out of range.
In this case it makes sense for the connection to break -- but the system doesn't handle it gracefully.

Environment: a cafe with a misconfigured WLAN, which NM will try to connect to unsuccessfully, causing other problems, until WLAN explicitly turned off.

Did a fresh log-in to system.

(Reported separately, a related problem)
It isn't good enough to successfully connect via DUN. Even with a working connection, NM will repeatedly try to connect with WLAN, pestering the user, and breaking a working connection.

Crash 1:
========

Connect via cell phone Bluetooth DUN.

Started Skype. Came up OK, could see people. Otherwise used network.
Saw skype notification that a buddy had logged in.
Very shortly thereafter, network died.
(was the buddy login and dying related? did they send me a message?)

No notification informed me the network was down.
Gnome NM icon still showing DUN connection,
ifconfig still shows IP address.

Still see my cell phone DUN device listed in Gnome NM table.

Try disconnect, reconnect. NM spins, fails.

Execute
 sudo restart bluetooth
Now can successfully re-connect via DUN.

Something SHOULD have informed me that something had died.

Crash 2:
========

Deliberately walked 30m or so away for a couple of minutes.
On return, found the
* network connection down, and
* under NM applet, no longer see the cell phone DUN device.

Note: this is the effect the bug report specifically refers to.
In the other crash the DUN device is still listed, although in both cases Bluetooth is evidently not functional.

What SHOULD happen is:

* a notification should pop up, saying the connection was lost.
* Bluetooth should be available to attempt re-connection

Cheers!

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.