Notes on ConnectedIO LTE modem + Raspberry Pi

gistfile1.txt

The following applies to using the ConnectedIO LT1001 and LT1002 LTE modems on Verizon
in North America with the Raspberry Pi running Raspbian Jessie Lite (04/10/2017).

These guidelines assume that the modem interface will be the primary connection to
the Internet under normal conditions (i.e. not initial setup or field servicing).

Initial Setup

Establish serial communications with the modem (e.g. minicom -D /dev/ttyACM0).
Check modem firmware version with AT%VER and decide if you want/need to upgrade.
Use the Windows update procedure described in the FAQ to update firmware (you'll
have to boot windows into the special "skip device driver signing authentication"
mode, so be sure to read the instructions before installing the Quanta flash upgrade
package.

Test connectivity with the LTE network with the supplied AT commands
AT%CMATT=1      // attach to the eNodeB and register on the network
AT%DPDNACT=1    // enable the data-plane

Once the data-plane command responds with OK, test IP connectivity to the LTE network
by rebooting the pi and allowing dhcpcd to auto configure the eth1 interface.

Once you're able to ping your 4G address (which you can with verizon-assigned static IP,
not sure about private IPs), apply the following changes:

0.) set the modem boot delay to zero (disable bootloader)
  AT%setbdelay=0

1.) disable dhcpcd service
  sudo systemctl disable dhcpcd.service
2.) edit the /etc/network/interfaces file as follows
  # interfaces(5) file used by ifup(8) and ifdown(8)

  # Please note that this file is written to be used with dhcpcd
  # For static IP, consult /etc/dhcpcd.conf and 'man dhcpcd.conf'

  # Include files from /etc/network/interfaces.d:
  source-directory /etc/network/interfaces.d

  auto lo
  iface lo inet loopback

  allow-hotplug eth0
  iface eth0 inet manual

  allow-hotplug eth1
  iface eth1 inet dhcp

  #allow-hotplug wlan0
  #iface wlan0 inet manual
  #    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf

  #allow-hotplug wlan1
  #iface wlan1 inet manual
  #    wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
4.) add the following line to /etc/dhcp/dhclient.conf
  reject 10.0.0.1;
  
  
5.) reboot and ensure that dhcp works on the eth1 interface

Notes:
dhclient seems to be more reliable than dhcpcd for some reason.
We reject offers from 10.0.0.1 because the modem will sometimes
offer addresses in this range when it isn't connected to the LTE network.
If we accept this address, we will not try anymore and will be stuck on
a useless IP range.