3G Modem MC8805:qmicli succesfuly connected but no IP after dhclient

[Bjørn Mork]

"Benoît" <benoitne at gmail.com> writes:

>   idVendor           0x413c Dell Computer Corp.
>   idProduct          0x81a3

OK, so that should be supported by qcserial.

>   bNumConfigurations      2
>   Configuration Descriptor:
>     bLength                 9
>     bDescriptorType         2
>     wTotalLength          204
>     bNumInterfaces          4
>     bConfigurationValue     1
>     iConfiguration          0
>     bmAttributes         0xe0
>       Self Powered
>       Remote Wakeup
>     MaxPower              500mA
>     Interface Descriptor:
>       bLength                 9
>       bDescriptorType         4
>       bInterfaceNumber        0
>       bAlternateSetting       0
>       bNumEndpoints           2
>       bInterfaceClass       255 Vendor Specific Class
>       bInterfaceSubClass    255 Vendor Specific Subclass
>       bInterfaceProtocol    255 Vendor Specific Protocol

[..]

>   Configuration Descriptor:
>     bLength                 9
>     bDescriptorType         2
>     wTotalLength           95
>     bNumInterfaces          2
>     bConfigurationValue     2
>     iConfiguration          0
>     bmAttributes         0xe0
>       Self Powered
>       Remote Wakeup
>     MaxPower              500mA
>     Interface Association:
>       bLength                 8
>       bDescriptorType        11
>       bFirstInterface        12
>       bInterfaceCount         2
>       bFunctionClass          2 Communications
>       bFunctionSubClass      14
>       bFunctionProtocol       0
>       iFunction               0
>     Interface Descriptor:
>       bLength                 9
>       bDescriptorType         4
>       bInterfaceNumber       12
>       bAlternateSetting       0
>       bNumEndpoints           1
>       bInterfaceClass         2 Communications
>       bInterfaceSubClass     14
>       bInterfaceProtocol      0


Right.  So, like all such devices, this will default to MBIM.  Did you
configure anything to make it switch to QMI? Which configuration is
currently active?  What did the kernel log when the device was
discovered and bound to drivers?

>
> tcpdump -vvv -i usbmon1
> tcpdump: listening on usbmon1, link-type USB_LINUX_MMAPPED (USB with
> padded Linux header), capture size 262144 bytes
> 11:19:09.096896 CONTROL SUBMIT to 1:3:0
> 11:19:09.097250 CONTROL COMPLETE from 1:3:0
> 11:19:09.097358 CONTROL SUBMIT to 1:2:0
> 11:19:09.097519 CONTROL COMPLETE from 1:2:0
> 11:19:09.097619 CONTROL SUBMIT to 1:1:0
> 11:19:09.097636 CONTROL COMPLETE from 1:1:0
> 11:19:13.197246 BULK SUBMIT to 1:3:1
> 11:19:13.197293 BULK COMPLETE from 1:3:1
> 11:19:21.531678 BULK SUBMIT to 1:3:1
> 11:19:21.531746 BULK COMPLETE from 1:3:1
>
> I don't know how this can help but I was able to do a tcpdump on the
> USB interface.
> I can see that when I launch dhclient the BULK SUBMIT to 1:3:1is sent
> and received BULK COMPLETE from 1:3:1

great! That dump doesn't help much though.  Use "tcpdump -xx -i usbmon1"
to see the buffer data. Or even better: Use tshark or wireshark to have
it all dissected into something readable.  You can also combine capturing
with tcpdump and dissecting with wireshark (on another host) if you are
limited to tcpdump on the capturing host for some reason. OpenWRT hosts
will have tcpdump, but not tshark for example.

> It confirms that the dhcp packet is going on the right interface but
> no reply.

Yup.

> I tried --wds-get-current-settings but it is not a valid command

Ah, OK.  I believe it is a recent addition.  Yes, very new and not yet
in a release AFAICS.  Sorry.  This is the commit id for reference:


commit 543cf5c93984139865f919e7348bff2b54c16f39
Author: Aleksander Morgado <aleksander at aleksander.es>
Date:   Thu Feb 26 10:48:06 2015 +0100

    qmicli,wds: new '--wds-get-current-settings' action
    
    Will print the IPv4 and IPv6 settings when connected. This information can be
    used to statically set the network interface configuration, instead of relying
    on a DHCP client.





Bjørn