Huawei E870 refuses to reconnect (on Natty)

[Martin Konôpka]

During my travel in train I was first in an area cover by 3G signal of my operator. Then I got into an area with only a 2G (GPRS or EDGE) signal. Afterwards I moved into an area without any GSM signal of my operator. Or at least my modem disconnected me. OK, that's expected in such areas.

In a minute or two I again entered area with 3G (indicated by blue LED blinking on the modem). I went on the NetworkManager icon and clicked on the connection name. I expected to be connected. Instead of it I just got message "Orange, you are now disconnected" or something like. (It was the kind of message which appear for few seconds in the upper right corner of desktop as a dark rectangle with text message.)

I tried again and again but it did not help and each time I got the message about the disconnected status. I stress that I was still in an area cover by a usable signal.

The only thing which helped to make a connection was to physically remove the modem (from the PC Express slot) and reinsert it into the slot. Then however I had to enter my PIN and only after accepting my PIN I could succesfully click on the NetworkManager connection name (i.e. I finally got the connection).

In my opinion it is unacceptable that user is forced to remove and reinsert the modem card and enter his/her PIN at every time when connection is lost due to weak signal.

Finally, I observed this behaviour reproducibly, at least two times during my travel.

My notebook is a Fujitsu-Siemens AMILO Pro V3205 (a 32-bit notebook) with ubuntu 11.04.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: modemmanager 0.4+git.20110124t203624.00b6cce-2ubuntu1
ProcVersionSignature: Ubuntu 2.6.38-13.53-generic 2.6.38.8
Uname: Linux 2.6.38-13-generic i686
Architecture: i386
Date: Fri Jan 13 21:33:52 2012
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Beta i386 (20110413)
ProcEnviron:
 LANGUAGE=en
 PATH=(custom, user)
 LANG=en_GB.utf8
 LC_MESSAGES=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: modemmanager
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[Sabin Iacob (iacobs)]

Huawei E173 and ZTE MF110 / Precise here, same story; it seems it's not device related after all.

I expect it to reconnect by itself when signal is back, BTW.

[Rafał Rzepecki (divided-mind)]

Same problem here, with ZTE MF195; relevant log fragment: https://gist.github.com/dividedmind/5091386
ttyACM0 is the data port, ttyACM1 is the aux port. Note the modem reporting reconnection (+CREG: 1) after mm has dropped the link.

I don't have the relevant log fragment at hand, but when forcing reconnection I noticed the modem is still sending PPP data (ie the connection hasn't dropped on its end), whereas mm is expecting AT negotiation at this point.

This problem is very annoying when you're in a place with weak coverage that comes and wanes. You end up having to pull modem every several minutes, just because of momentary loss of connection. I'll also note that Windows handles this gracefully, with the bundled connection manager and without it (ie. vanilla RAS, just the modem driver).