MC7455/EM7455 dependencies and protocols

Aleksander Morgado aleksander at aleksander.es
Wed Mar 22 08:29:58 UTC 2017


On 21/03/17 23:23, Tim Harvey wrote:
>>>> root at ventana:~# qmicli -d /dev/cdc-wdm0 --dms-get-ids
>>>> [21 Mar 2017, 14:00:22] -Warning ** Error reading from istream: Error
>>>> reading from file descriptor: Input/output error
>>>> error: couldn't create client for the 'dms' service: CID allocation
>>>> failed in the CTL client: Transaction timed out
>>> Aleksander was running into a similar issue with 73XX devices, let's
>>> see how that plays out.
>> But I didn't see the problem on MC7455; not a single time :/ Can't
>> confirm it's the same issue.
>>
> Looks like I had a bad modem. I had a 2nd MC7455 and it seems to
> behave just fine.
> 
> I have found that this modem (or Google Fi carrier I was testing
> with?) is not supporting DHCP but using 'qmicli -d /dev/cdc-wdm0
> --client-no-release-cid --client-cid=35 --wds-get-current-settings' to
> obtain the IPv4 settings and manually configuring them worked fine.

MC7455 running QMI mode uses "raw-ip" as link layer protocol (instead of
ethernet frames); and most DHCP clients out there don't support raw IP
interfaces yet; so doing static IP addressing as you did is the easiest
way to go (that is what ModemManager does, for example).

-- 
Aleksander
https://aleksander.es


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