Re: Sierra Wireless MC7750 / MM 0.7.990 / NM 0.9.8

[Dan Williams <dcbw redhat com>]

On Wed, 2013-04-10 at 09:32 +0200, Aleksander Morgado wrote:
> > It took me a little while, but I put together recent builds with the 'aleksander/current-capabilities' 
> > branch merged back into trunk.  I now have launchpad set up to do daily builds.
> >
> > If anyone else is on debian/ubuntu/mint, you can pull the builds from:
> >
> > https://code.launchpad.net/~dwa/+archive/network-manager-snapshots
> >
> > As for results, this is much better than what I had before.  I am NOT getting the error I used to get 
> > ("Error: Connection activation failed: The connection was not a 3GPP2 connection.").  So the 
> > 'aleksander/current-capabilities' branch seems to have fixed this.
>
>
> Good to know. Dan, what's your take on that patch?

I thought we'd merged that already :)  I just looked again, and it still
looks good.  It's certainly an improvement, the only thing we still need
to fix is how to handle multi-mode devices that can switch between 3GPP
and 3GPP2 at runtime (eg, UML290 or UMW190).

> > For a little while this afternoon, I thought everything was working perfectly --- complete with the 
> > ability to connect/disconnect through the GUI.  Recall, however, that geographically, I am within the 
> > "Verizon Extended Coverage Area" in which Verizon states "certain conditions may cause your service to 
> > connect to 3G in this Area."
> >
> > I suspect that whenever I get a 3G EVDO connection, everything is fine, but that I'm unable to get a 4G 
> > LTE connection.  The error is as follows:
> >
> > > Apr  9 16:45:40 bree ModemManager[1001]: <info>  verbose call end reason (6,51): [3gpp] ipv6-only-allowed
> >
> > I take it to mean that Verizon only wants to give me an IPV6 connection over 4G LTE?  That's what this 
> > article seems to imply:
> >
> > > LTE devices must support IPv6, says Verizon
> > > IPv4 support for Verizon 4G devices is optional
> > > By Brad Reed, Network World
> > > June 10, 2009 01:37 PM ET 
> > > http://www.networkworld.com/news/2009/061009-verizon-lte-ipv6.html
>
> Dan may know more about the Verizon LTE status, no idea here.

I see below you're using the "vzwims" APN, which is indeed IPv6 only.
Don't use that one, the normal LTE data APN is "vzwinternet".  Welcome
to 3GPP and enthusiastic over-configurability.

> > I'm reposting my command-line modem manager script:
> >
> > #!/bin/sh
> > date ; echo "\nCurrent Modem Configuration:"
> > mmcli -m /org/freedesktop/ModemManager1/Modem/0
> > mmcli -m /org/freedesktop/ModemManager1/Modem/0 --set-allowed-modes=ANY --set-preferred-mode=3G
> > mmcli -m /org/freedesktop/ModemManager1/Modem/0 -e
> > date ; echo "\nCurrent Modem Configuration:"
> > mmcli -m /org/freedesktop/ModemManager1/Modem/0
> > mmcli -m 0 --simple-connect="apn=vzwims"
> > date ; echo "\nObtaining DHCP lease"
> > dhclient -d -4 wwan0
> >
> > Some questions:
> >
> > (1) How can I modify the "mmcli -m 0 --simple-connect="apn=vzwims" line for IPv6 support?  Do I need to 
> > ditch --simple-connect syntax and deal directly with bearers, etc.?  If so, how?

Are you 100% sure you want to use vzwims?

> You can use any of the --create-bearer options directly in
> --simple-connect. In your case, it would be something like:

> $> mmcli -m 0 --simple-connect="apn=vzwims,ip-type=ipv6"
>
>
> > (2) It is possible to force 3G EVDO even though the device is 4G LTE capable?  Particularly given the 
> > branch.
>
> You can try to use "mmcli -m 0 --set-allowed-modes=3g". Although you may
> have problems with the 3GPP vs 3GPP2 connection settings again... We
> should probably try to avoid this issue in NM somehow.

I'm curious about whether this works or not; I should try with the
UML290.  There used to be an issue where you needed to *also* switch the
HDR authentication protocol to HRPD instead of the LTE-required eHRPD; I
don't know if they've solved this generally by now.

> > (3) In a nutshell, what's the overall state of IPv6 support in the codebase 
> > (modemmanager/networkmanager/gui)?  I note that there's an IPv6 tab in the network manager GUI for wired 
> > and wifi connections, but not for broadband.  Networkmanager itself and the gui are 0.9.8 built against 
> > current modemmanager, rather that the actual latest from git.
>
> For mobile broadband modems using a net interface, I'm not sure if there
> is any big issue with IPv6. Although I haven't tested it myself.

NetworkManager doesn't yet have support for it, but I've had branches
floating around for a while.  We fully intend to support this when we
can get a device that actually works.  No device so far has successfully
handled IPv6 autoconfiguration for various reasons [1] [2] but the
MC7750 might be a good one to try.

Dan

[1] ppp-based devices can only negotiate the IPv6 address and then must
listen for router advertisements over the PPP interface for the DNS
addresses, but most firmware doesn't yet support generating the RAs.  So
you have to use static IPv6 DNS servers from Google or otherwise.

[2] dhcp-based devices don't always implement the right options either,
and the IPv6 address generated by the kernel may not be the one the
device is actually using due to problems with synchronizing the MAC
address between the driver and the firmware.