Huawei MS2732h-517 in NCM mode

Routers
6

Resurfacing this thread in hopes that some new information might help find a solution.

So, I was able to get the Huawei MS2732h-517 working with ‘clean’ firmware on an MT300N. Here was the procedure:

  1. Flash with GL.iNet download center

  2. opkg update & install wget usbutils kmod-usb2 kmod-usb-ohci kmod-usb-uhci kmod-usb-serial kmod-usb-serial-option kmod-usb-serial-wwan usb-modeswitch luci-proto-3g kmod-usb-core chat ppp libusb comgt comgt-ncm kmod-usb-net-huawei-cdc-ncm socat minicom

  3. Reboot

  4. Check USB modem is recognized:
    root@OpenWrt:~# lsusb
    Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
    Bus 001 Device 003: ID 12d1:1506 Huawei Technologies Co., Ltd. E398 LTE/UMTS/GSM Modem/Networkcard
    Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

  5. Check correct driver assigned:
    root@OpenWrt:~# lsusb -t
    /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ohci-platform/1p, 12M
    /: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-platform/1p, 480M
    |__ Port 1: Dev 3, If 0, Class=Vendor Specific Class, Driver=option, 480M
    |__ Port 1: Dev 3, If 1, Class=Vendor Specific Class, Driver=option, 480M
    |__ Port 1: Dev 3, If 2, Class=Vendor Specific Class, Driver=option, 480M
    |__ Port 1: Dev 3, If 3, Class=Vendor Specific Class, Driver=huawei_cdc_ncm, 480M

  6. Add wwan0 interface to WAN firewall zone.

  7. Specify DNS servers to use for wwan0 interface (peerdns set to 0)

  8. Issue AT commands to set APN and establish an LTE connection:
    root@OpenWrt:~# socat - /dev/ttyUSB2,crnl
    AT+CGDCONT=1,“IP”,“fast.t-mobile.com”
    OK
    AT^NDISDUP=1,1,
    OK
    ^NDISSTAT:1,“IPV4”

  9. Acquire DHCP lease on wwan0
    root@OpenWrt:~# udhcpc --interface=wwan0 -q
    udhcpc (v1.24.1) started
    Sending discover…
    Sending select for 22.83.137.140…
    Lease of 22.83.137.140 obtained, lease time 518400
    udhcpc: ifconfig wwan0 22.83.137.140 netmask 255.255.255.248 broadcast +
    udhcpc: setting default routers: 22.83.137.137

After step 9, the router has an active internet connection with name resolution, as do its LAN clients. EDIT:
I can also follow these steps and get this connection to work on an MT300N-V1 with stock gl-inet firmware (GL.iNet download center). But when I try to do the same 9 steps on an MT300N-V2 with stock gl-inet firmware (GL.iNet download center), I get all the way through step 8, but when I try to acquire DHCP on wwan0 at step 9, it attempts 3 times and then hangs:

root@RVIT_client0:/# udhcpc --interface=wwan0 -q
udhcpc: started, v1.25.1
udhcpc: sending discover
udhcpc: sending discover
udhcpc: sending discover

My guess is there is some package installed on the gl-inet firmware that is preventing DHCP assignment on wwan0 (mwan3?). Any ideas on how I can get this device to pass its active connection to the router?