Touble Connecting with PPP in Ubuntu

Hi,

I’m having trouble getting an HL7800-M modem (several actually, all the units I have access to are behaving the same way) up and connected with PPP.

I know that the modems are connected to the network because I can use KHTTPGET with no problem, but I can’t get a network interface up and usable in the Linux environment. Additionally I’ve tested the SIMs with other modems and they have no issue bringing up a connected with pppd

I’ve been following this tutorial, but I’m still stuck.
I’ve modified it slightly so as to not create a defaultroute, and to use PDP 3 since we’re using Verizon SIMs

I run sudo pppd call hl7800test and when I’m monitoring the syslog I can see what looks like a valid connection that immediately disconnects.

Aug 4 15:46:46 protosled pppd[262057]: local IP address 100.68.176.66
Aug 4 15:46:46 protosled pppd[262057]: remote IP address 10.64.64.64
Aug 4 15:46:46 protosled pppd[262057]: primary DNS address 198.224.156.135
Aug 4 15:46:46 protosled pppd[262057]: secondary DNS address 198.224.157.135
Aug 4 15:46:46 protosled pppd[262057]: Script /etc/ppp/ip-up started (pid 262068)
Aug 4 15:46:46 protosled NetworkManager[647]: [1659628006.2084] device (ppp0): state change: unmanaged → unavailable (reason ‘connection-assumed’, sys-iface-state: ‘external’)
Aug 4 15:46:46 protosled NetworkManager[647]: [1659628006.2126] device (ppp0): state change: unavailable → disconnected (reason ‘none’, sys-iface-state: ‘external’)
Aug 4 15:46:46 protosled systemd-networkd[631]: ppp0: Link UP
Aug 4 15:46:46 protosled systemd-networkd[631]: ppp0: Gained carrier
Aug 4 15:46:46 protosled pppd[262057]: rcvd [IPCP TermReq id=0x4 “Could not determine local IP address”]
Aug 4 15:46:46 protosled pppd[262057]: IPCP terminated by peer (Could not determine local IP address)
Aug 4 15:46:46 protosled systemd-networkd[631]: ppp0: Link DOWN
Aug 4 15:46:46 protosled pppd[262057]: Connect time 0.0 minutes.
Aug 4 15:46:46 protosled systemd-networkd[631]: ppp0: Lost carrier
Aug 4 15:46:46 protosled pppd[262057]: Sent 0 bytes, received 40 bytes.
Aug 4 15:46:46 protosled pppd[262057]: sent [IPCP TermAck id=0x4]
Aug 4 15:46:46 protosled NetworkManager[647]: [1659628006.2236] device (ppp0): state change: disconnected → unmanaged (reason ‘connection-assumed’, sys-iface-state: ‘external’)
Aug 4 15:46:46 protosled pppd[262057]: Script /etc/ppp/ip-up finished (pid 262068), status = 0x0
Aug 4 15:46:46 protosled pppd[262057]: Script /etc/ppp/ip-down started (pid 262083)
Aug 4 15:46:46 protosled pppd[262057]: Script /etc/ppp/ip-down finished (pid 262083), status = 0x0

As such, I don’t even have any time to test the interface to see if there’s a network connection before it tears itself down.

Is there some additional setup parameter that I’m missing? Or is this something on the other end of the connection that’s rejecting my connection attempt?

For reference, the host system is running Ubuntu 20.04 with pppd version 2.4.7.

I’ve attached the exact configuration files I’m using as well as the entire syslog output for the command gathered during the connection attempt.
hl7800_ppp.tgz (1.6 KB)

Dear @KPA ,

Welcome to Sierra community!

  • Which FW version is your module running? If it is not latest, please refer to the following link to download and upgrade the module to the latest then recheck whether the problem is resolved
  • Besides, according to AirPrime HL78xx Establishing a PPP Session with a Linux Host document, hl78xx-chat file contains the following content:

However, your hl7800test-chat shows

image

Please try to correct the highlighted parameter then recheck the problem

Thanks