Re: Looking for advice about using NM with a Sprint U301 modem

[Daenyth Blank <daenyth gmail com>]

On Wed, Jun 2, 2010 at 08:12, Daenyth Blank <daenyth gmail com> wrote:
> On Wed, Jun 2, 2010 at 03:16, Dan Williams <dcbw redhat com> wrote:
>> On Thu, 2010-05-27 at 12:04 -0400, Daenyth Blank wrote:
>>> Hi all,
>>>
>>> I'm trying to find out some information regarding the Sprint U301 3G
>>> modem. Our use case for it is that it will be attached to an embedded
>>> machine running ubuntu with networkmanager, in addition to our
>>> software. I've been trying to get this modem to connect reliably and
>>> am having some issues with it. I've added a udev rule so that the
>>> usbserial driver is given the correct vendor/product information, and
>>> it connects automatically on boot, but not reliably. Some boots it
>>> does not connect at all and won't until I reboot. Sometimes it
>>> disconnects while the machine is running. If it disconnects either by
>>> itself or from deactivating the connection, it will not connect again
>>> and needs a reboot. The nm/mm logs say that serial requests are timing
>>> out when it's in the non-connected state. I haven't been able to
>>> recover from the disconnected state with anything about a reboot.
>>>
>>> Is there anything we can do with this device to increase reliability?
>>> Failing that, can you recommend a usb Sprint 3G modem that will be
>>> more reliable? If there are none, do you have any recommendations for
>>> any brand of 3G modem that will work well in this situation? The boxes
>>> will be deployed where manual access is not easy, so it needs to be
>>> able to connect and recover from disconnections automatically, or at
>>> least in a way that can be scripted easily.
>>
>> You're certainly not going to be able to get the WiMAX part of the
>> device working automatically since we dont' have drivers for the Beceem
>> chipset of the WiMAX side.  However, the EVDO side should work with
>> cdc-acm, so if you have to use 'usb-serial' there's already something
>> wrong.
>>
>> I suspect you need to use usb_modeswitch to eject the fake CD that the
>> device provides too, correct?
>>
>> Honestly, UTStarcom-based devices (which the 300 and 301 are rebrands
>> of) often don't work that well as you've found out.  I'd recommend a
>> Sierra device instead, as Sierra is also very active in Linux kernel
>> development and has great support for their devices.
>>
>> Dan
>>
>>
>
> Thanks Forest, Dan. I'm going to recommend to our client that we use
> the Sierra cards. Appreciate the advice!
>

I'm looking into the 598 now, and I'm having a little trouble getting
NM to recognize it. I plug in the device and I can see by using dmesg
that the sierra driver gets loaded, but when I run
nm-connection-editor and try to edit the connection, it doesn't get
listed in the device dropdown. Is there anything I have to do to get
it recognized? I also haven't been able to find any good guides on
setting it up. I'm running Ubuntu Karmic right now.

Thanks,