Connection established but no data transfers using QMI

Raspberry Pi Network HATs 3G/4G&LTE Base HAT
1

Hello,
I’ve successfully connected my Sixfab LTE Base HAT and Quectel EC25G to transfer data via QMI, but it has now stopped allowing data transfer over the LTE/wwan0 interface. The quectel-CM process seems to connect to the network because it gets an IP address, but I can’t use the wwan0 interface to transfer any data or ping. When I run a fresh install of everything it seems to connect to the LTE network, but I can’t transfer any data.

What would cause this problem?

The problems started when I tried to manage the network interface directly with:

ifconfig wwan0 down

This was intended, but when I issued:

ifconfig wwan0 up

It never came back up. After trying unsuccessfully to restart the network many ways (details omitted), I performed a clean reinstall of everything, again following the tutorials. Unfortunately the network seems to be connecting, but not allowing transfer of any user data:

$ ping -I wwan0 -c 5 8.8.8.8
PING 8.8.8.8 (8.8.8.8) from 100.72.175.244 wwan0: 56(84) bytes of data.

--- 8.8.8.8 ping statistics ---
5 packets transmitted, 0 received, 100% packet loss, time 180ms

However the LTE network seems to get an IP address and I can ping it locally:

$ ping -I wwan0 -c 5 100.72.175.244
PING 100.72.175.244 (100.72.175.244) from 100.72.175.244 wwan0: 56(84) bytes of data.
64 bytes from 100.72.175.244: icmp_seq=1 ttl=64 time=0.144 ms
64 bytes from 100.72.175.244: icmp_seq=2 ttl=64 time=0.165 ms
64 bytes from 100.72.175.244: icmp_seq=3 ttl=64 time=0.141 ms
64 bytes from 100.72.175.244: icmp_seq=4 ttl=64 time=0.167 ms
64 bytes from 100.72.175.244: icmp_seq=5 ttl=64 time=0.148 ms

--- 100.72.175.244 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 131ms
rtt min/avg/max/mdev = 0.141/0.153/0.167/0.010 ms

Here’s the interface that appears to be up (but no data transfer, ex: ping):

$ ifconfig wwan0
wwan0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST>  mtu 1360
        inet 100.72.175.244  netmask 255.255.255.248  destination 100.72.175.244
        inet6 fe80::b4ee:760f:269a:ef85  prefixlen 64  scopeid 0x20<link>
        unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  txqueuelen 1000  (UNSPEC)
        RX packets 4  bytes 1224 (1.1 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 367  bytes 27904 (27.2 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Hardware:

Raspberry Pi 3B+
Quectel EC25 Mini PCle 4G/LTE Module - EG25-G (Global)
Raspberry Pi 3G/4G & LTE Base HAT
Sixfab Connect SIM

Logs from the quectel-CM process:

~/files/quectel-CM $ sudo ./quectel-CM -s super
[08-21_11:44:29:680] Quectel_QConnectManager_Linux_V1.6.0.12
[08-21_11:44:29:681] Find /sys/bus/usb/devices/1-1.1.2 idVendor=0x2c7c idProduct=0x125, bus=0x001, dev=0x004
[08-21_11:44:29:681] Auto find qmichannel = /dev/cdc-wdm0
[08-21_11:44:29:681] Auto find usbnet_adapter = wwan0
[08-21_11:44:29:681] netcard driver = qmi_wwan, driver version = 5.10.52-v7+
[08-21_11:44:29:682] ioctl(0x89f3, qmap_settings) failed: Operation not supported, rc=-1
[08-21_11:44:29:682] Modem works in QMI mode
[08-21_11:44:29:698] cdc_wdm_fd = 7
[08-21_11:44:29:801] Get clientWDS = 17
[08-21_11:44:29:835] Get clientDMS = 1
[08-21_11:44:29:869] Get clientNAS = 3
[08-21_11:44:29:903] Get clientUIM = 2
[08-21_11:44:29:938] Get clientWDA = 1
[08-21_11:44:29:972] requestBaseBandVersion EG25GGBR07A08M2G
[08-21_11:44:30:107] requestGetSIMStatus SIMStatus: SIM_READY
[08-21_11:44:30:107] requestSetProfile[1] super///0
[08-21_11:44:30:175] requestGetProfile[1] super///0
[08-21_11:44:30:210] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
[08-21_11:44:30:244] requestQueryDataCall IPv4ConnectionStatus: DISCONNECTED
[08-21_11:44:30:245] ifconfig wwan0 down
[08-21_11:44:30:262] ifconfig wwan0 0.0.0.0
[08-21_11:44:30:310] requestSetupDataCall WdsConnectionIPv4Handle: 0x872c3e00
[08-21_11:44:30:446] change mtu 1500 -> 1360
[08-21_11:44:30:447] ifconfig wwan0 up
[08-21_11:44:30:460] busybox udhcpc -f -n -q -t 5 -i wwan0
udhcpc: started, v1.30.1
No resolv.conf for interface wwan0.udhcpc
udhcpc: sending discover
udhcpc: sending discover
udhcpc: sending discover
udhcpc: sending discover
udhcpc: sending discover
udhcpc: no lease, failing
[08-21_11:44:46:083] File:ql_raw_ip_mode_check Line:105 udhcpc fail to get ip address, try next:
[08-21_11:44:46:083] ifconfig wwan0 down
[08-21_11:44:46:098] echo Y > /sys/class/net/wwan0/qmi/raw_ip
[08-21_11:44:46:099] ifconfig wwan0 up
[08-21_11:44:46:113] busybox udhcpc -f -n -q -t 5 -i wwan0
udhcpc: started, v1.30.1
No resolv.conf for interface wwan0.udhcpc
udhcpc: sending discover
udhcpc: sending select for 100.72.175.244
udhcpc: lease of 100.72.175.244 obtained, lease time 7200
Too few arguments.
Too few arguments.
[08-21_11:50:06:568] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
[08-21_11:50:37:236] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
[08-21_11:51:06:334] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
[08-21_11:51:06:368] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
[08-21_12:02:39:900] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
[08-21_12:02:50:400] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
[08-21_12:15:32:332] requestRegistrationState2 MCC: 310, MNC: 410, PS: Attached, DataCap: LTE
2

Hi @thrasher ,

Thanks for the detailed logs.
Make sure the SIM is active and also if you have exceeded the ‘monthly limit’, can you update it to ‘unlimited’ and try?

Sixfab-Connect-SIM-Data-Management
Sixfab-Connect-SIM-Data-Management1115×489 15.2 KB

3

That has fixed the problem! I set the Monthly Limit to Unlimited, and also pulled out and re-seated the SIM card (with power off). Rebooted, and now I’m able to send user data over the network again.

I did notice that I have not hit my 100MB limit as previously set for the month of August. The sim was registered in July, and only had <10 MB of data usage then. Currently the dashboard is showing 17.03MB of usage for August (pic below).

Thank you!
-Jason

$ ping -I wwan0 -c 5 8.8.8.8
PING 8.8.8.8 (8.8.8.8) from 100.73.142.121 wwan0: 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=109 time=282 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=109 time=159 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=109 time=188 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=109 time=152 ms
64 bytes from 8.8.8.8: icmp_seq=5 ttl=109 time=185 ms

--- 8.8.8.8 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 8ms
rtt min/avg/max/mdev = 152.291/193.133/281.573/46.421 ms

and

$ curl --interface wwan0 https://www.example.com/
<!doctype html>
<html>
<head>
    <title>Example Domain</title>
[SNIP]

Screen Shot 2021-08-21 at 4.47.53 PM
Screen Shot 2021-08-21 at 4.47.53 PM1920×661 55.2 KB