mbim Bearer reports IP_METHOD_DHCP when namesservers are missing

[Aleksander Morgado]

On Thu, Dec 3, 2015 at 11:18 AM, Andreas Fett <andreas.fett at secunet.com> wrote:
> In src/mm-bearer-mbim.c: ip_configuration_query_ready()
> the bearer will set IP_METHOD_DHCP if ipv4dnsservercount is zero,
> it does so regardless of any present IP configuration (which is visible
> in the bearer object).
>
> Unfortunately some (or all?) mbim modems do not support DHCP, and I have
> a scenario at hand where the provider does not supply any DNS servers.
>

Not all, just some.

> I noticed that other bearer implementations (eg.
> mm-broadband-bearer-mbm) will report IP_METHOD_STATIC even if no
> nameserver info could be acquired.
>
> Which is the correct way to deal with this? Patch the mibm bearer
> to report IP_METHOD_STATIC if it gets at least ip and gateway or
> just ignore the IP_METHOD_XXX if we find all info we need in the bearer?

Gateway should also not be mandatory. Should we maybe just say STATIC
if we get an IP address reported by the modem?

What do others think? Is there any MBIM modem out there not reporting
any IP settings when queried and therefore do require DHCP?

One thing we could do is to expose in the bearer IP config all the
available fields, even if we end up  requesting DHCP, but with the new
logic we would only be requesting DHCP if there's no IP, and not sure
if the modem will ever report any other setting when IP is not even
reported.

-- 
Aleksander
https://aleksander.es