Quectel EC25A refusing to issue ipv4

Sun Sep 2 04:37:56 UTC 2018

Sorry if this has been covered and my search skills on the mailing list 
archive failed me.

I have a Quectel EC25AFAR05A04M4G (rev. 10000 according to mmcli) modem 
which gets an ipv4 address in windows as follows:

Mobile Broadband adapter Mobile Broadband Connection 2:

    Connection-specific DNS Suffix  . :
    IPv6 Address. . . . . . . . . . . : 
2607:fb90:4ae9:5152:2d4a:269:4c79:3aeb
    IPv6 Address. . . . . . . . . . . : 
2607:fb90:4ae9:5152:6581:8704:bcc7:e874
    Temporary IPv6 Address. . . . . . : 
2607:fb90:4ae9:5152:a1cc:1474:277:1844
    IPv4 Address. . . . . . . . . . . : 26.126.253.115
    Subnet Mask . . . . . . . . . . . : 255.255.255.248
    Default Gateway . . . . . . . . . : 
2607:fb90:4ae9:5152:91ab:8859:c3a4:acc8
fe80::91ab:8859:c3a4:acc8%26
                                        26.126.253.116

This tells me that my carrier and my device support both ipv4 and ipv6.

My current setup includes libmbim-glib-dev 1.16.0-1 from debian/testing 
and I'm using 1.4.0-690-gde362e9

mmcli says the IP supported is "ipv4, ipv6, ipv4v6".  I've tried the 
--wds-set-ip-family=4 option that was recently added like so:

# qmicli -d /dev/cdc-wdm0 --wds-set-ip-family=4 --client-no-release-cid -v
[01 Sep 2018, 21:10:03] [Debug] [/dev/cdc-wdm0] Opening device with 
flags 'auto'...
[01 Sep 2018, 21:10:03] [Debug] [/dev/cdc-wdm0] loaded driver of cdc-wdm 
port: qmi_wwan
[01 Sep 2018, 21:10:03] -Warning ** [/dev/cdc-wdm0] requested auto mode 
but no MBIM QMUX support available
[01 Sep 2018, 21:10:03] [Debug] QMI Device at '/dev/cdc-wdm0' ready
[01 Sep 2018, 21:10:03] [Debug] [/dev/cdc-wdm0] Assuming service 'wds' 
is supported...
[01 Sep 2018, 21:10:03] [Debug] [/dev/cdc-wdm0] Allocating new client ID...
[01 Sep 2018, 21:10:03] [Debug] [/dev/cdc-wdm0] sent message...
<<<<<< RAW:
<<<<<<   length = 16
<<<<<<   data   = 01:0F:00:00:00:00:00:01:22:00:04:00:01:01:00:01

[01 Sep 2018, 21:10:03] [Debug] [/dev/cdc-wdm0] sent generic request 
(translated)...
<<<<<< QMUX:
<<<<<<   length  = 15
<<<<<<   flags   = 0x00
<<<<<<   service = "ctl"
<<<<<<   client  = 0
<<<<<< QMI:
<<<<<<   flags       = "none"
<<<<<<   transaction = 1
<<<<<<   tlv_length  = 4
<<<<<<   message     = "Allocate CID" (0x0022)
<<<<<< TLV:
<<<<<<   type       = "Service" (0x01)
<<<<<<   length     = 1
<<<<<<   value      = 01
<<<<<<   translated = wds

[01 Sep 2018, 21:10:06] [Debug] [/dev/cdc-wdm0] received message...
<<<<<< RAW:
<<<<<<   length = 25
<<<<<<   data   = 
01:18:00:80:03:03:02:AA:0C:20:00:0C:00:02:04:00:00:00:00:00:01:02:00:C8:08

[01 Sep 2018, 21:10:06] [Debug] [/dev/cdc-wdm0] received generic 
response (translated)...
<<<<<< QMUX:
<<<<<<   length  = 24
<<<<<<   flags   = 0x80
<<<<<<   service = "nas"
<<<<<<   client  = 3
<<<<<< QMI:
<<<<<<   flags       = "response"
<<<<<<   transaction = 3242
<<<<<<   tlv_length  = 12
<<<<<<   message     = "Get Signal Strength" (0x0020)
<<<<<< TLV:
<<<<<<   type       = "Result" (0x02)
<<<<<<   length     = 4
<<<<<<   value      = 00:00:00:00
<<<<<<   translated = SUCCESS
<<<<<< TLV:
<<<<<<   type       = "Signal Strength" (0x01)
<<<<<<   length     = 2
<<<<<<   value      = C8:08
<<<<<<   translated = [ strength = '-56' radio_interface = 'lte' ]

[01 Sep 2018, 21:10:06] [Debug] [/dev/cdc-wdm0] No transaction matched 
in received message

error: couldn't create client for the 'wds' service: CID allocation 
failed in the CTL client: Transaction timed out

----->8----

I've separately tried addressing this through /etc/qmi-network.conf by 
making the content as follows:

APN=network
IP-TYPE=4

Then I tried to start the network (with and without the ip-type=4 
line).  With the ip-type=4 line I get the following:

loading profile at /etc/qmi-network.conf...
/usr/local/bin/qmi-network: 2: /etc/qmi-network.conf: ip-type=4: not found
     APN: internet
     APN user: unset
     APN password: unset
     qmi-proxy: no
Checking data format with 'qmicli -d /dev/cdc-wdm0 --wda-get-data-format 
'...
[01 Sep 2018, 21:24:01] -Warning ** [/dev/cdc-wdm0] requested auto mode 
but no MBIM QMUX support available
Device link layer protocol retrieved: raw-ip
Getting expected data format with 'qmicli -d /dev/cdc-wdm0 
--get-expected-data-format'...
[01 Sep 2018, 21:24:01] -Warning ** [/dev/cdc-wdm0] requested auto mode 
but no MBIM QMUX support available
Expected link layer protocol retrieved: raw-ip
Device and kernel link layer protocol match: raw-ip
Starting network with 'qmicli -d /dev/cdc-wdm0 
--wds-start-network=apn='internet'  --client-no-release-cid '...
[01 Sep 2018, 21:24:01] -Warning ** [/dev/cdc-wdm0] requested auto mode 
but no MBIM QMUX support available
Saving state at /tmp/qmi-network-state-cdc-wdm0... (CID: 24)
Saving state at /tmp/qmi-network-state-cdc-wdm0... (PDH: 2267257648)
Network started successfully

Then I do something like

dhclient -4 wwp0s29u1u1u4i4

which returns immediately

Then I do an ip addr show and see I have, much to my dismay only an ipv6 
address.

We have a few thousand of these quectels on order which are going to be 
in embedded devices so I guess I could have some massive ipv6to4 bridge 
running but I'd rather not and I'd much rather have an ipv6 AND ipv4 
address like I can get on windows - I'd also be ok with only an ipv4 
address. I'm probably not ok however, with exclusively an ipv6.

Any clues on how I can get this device to register an ipv4 address?  The 
carrier is T-Mobile btw, if that makes a difference.

Thanks!