cellular modem: pppd modem hangup

Question

I am trying to establish a cellular connection to Verizon through my Multitech Multiconnect Dragonfly (MTQ-LVW3-B02). I am able to connect to Verizons network and get an IP address. The problem is that after a few seconds the modem hangs up the connection.

Mar 26 19:26:57 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm- ppp-plugin: (nm_ip6_up): sending IPv6 config to NetworkManager... Mar 26 19:26:57 localhost NetworkManager[2071]: Script /etc/ppp/ipv6-up started (pid 10367) Mar 26 19:26:57 localhost NetworkManager[2071]: Script /etc/ppp/ipv6-up finished (pid 10367), status = 0x0 Mar 26 19:26:57 localhost pppd[10353]: sent [IPCP ConfReq id=0x3 <addr
100.113.208.106> <ms-dns1 198.224.160.135> <ms-dns2 198.224.164.135>] Mar 26 19:26:57 localhost pppd[10353]: rcvd [IPV6CP ConfAck id=0x2 <addr fe80::0000:0052:19b4:d801>] Mar 26 19:26:57 localhost pppd[10353]: local LL address fe80::0000:0052:19b4:d801 Mar 26 19:26:57 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_ip_up): ip-up event Mar 26 19:26:57 localhost pppd[10353]: remote LL address fe80::6dac:d335:a09b:525b Mar 26 19:26:57 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_ip_up): sending IPv4 config to NetworkManager... Mar 26 19:26:57 localhost NetworkManager[2071]: Script /etc/ppp/ip-up started (pid 10369) Mar 26 19:26:57 localhost pppd[10353]: Script /etc/ppp/ipv6-up started (pid 10367) Mar 26 19:26:57 localhost pppd[10353]: Script /etc/ppp/ipv6-up finished (pid 10367), status = 0x0 Mar 26 19:26:57 localhost pppd[10353]: rcvd [IPCP ConfAck id=0x3 <addr 100.113.208.106> <ms-dns1 198.224.160.135> <ms-dns2 198.224.164.135>] Mar 26 19:26:57 localhost NetworkManager[2071]: <info> [1522092417.0839] ppp-manager: (IPv4 Config Get) reply received. Mar 26 19:26:57 localhost pppd[10353]: local IP address 100.113.208.106 Mar 26 19:26:57 localhost pppd[10353]: remote IP address 100.113.208.106 Mar 26 19:26:57 localhost pppd[10353]: primary DNS address 198.224.160.135 Mar 26 19:26:57 localhost pppd[10353]: secondary DNS address 198.224.164.135 Mar 26 19:26:57 localhost pppd[10353]: Script /etc/ppp/ip-up started (pid 10369) Mar 26 19:26:57 localhost pppd[10353]: Script /etc/ppp/ip-up finished (pid 10369), status = 0x0 Mar 26 19:26:57 localhost NetworkManager[2071]: Script /etc/ppp/ip-up finished (pid 10369), status = 0x0 Mar 26 19:26:57 localhost NetworkManager[2071]: <info> [1522092417.1068] policy: set 'vzw' (ppp0) as default for IPv4 routing and DNS Mar 26 19:26:57 localhost dnsmasq[2407]: using nameserver 198.224.160.135#53(via ppp0) Mar 26 19:26:57 localhost dnsmasq[2407]: using nameserver 198.224.164.135#53(via ppp0) Mar 26 19:26:57 localhost nm-dispatcher: req:4 'up' [ppp0]: new request (1 scripts) Mar 26 19:26:57 localhost nm-dispatcher: req:4 'up' [ppp0]: start running ordered scripts... Mar 26 19:26:57 localhost NetworkManager[2071]: <info> [1522092417.1530] policy: set 'vzw' (ppp0) as default for IPv6 routing and DNS Mar 26 19:27:03 localhost pppd[10353]: Modem hangup Mar 26 19:27:03 localhost pppd[10353]: Connect time 0.1 minutes. Mar 26 19:27:03 localhost pppd[10353]: Sent 1302 bytes, received 1196 bytes. Mar 26 19:27:03 localhost pppd[10353]: Script /etc/ppp/ip-down started (pid 10523) Mar 26 19:27:03 localhost pppd[10353]: cif6addr: ioctl(SIOCDIFADDR): No such address Mar 26 19:27:03 localhost NetworkManager[2071]: Script /etc/ppp/ip-down started (pid 10523) Mar 26 19:27:03 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 8 / phase 'network' Mar 26 19:27:03 localhost pppd[10353]: Script /etc/ppp/ipv6-down started (pid 10527) Mar 26 19:27:03 localhost NetworkManager[2071]: Script /etc/ppp/ipv6-down started (pid 10527) Mar 26 19:27:03 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 5 / phase 'establish' Mar 26 19:27:03 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 11 / phase 'disconnect' Mar 26 19:27:03 localhost pppd[10353]: Connection terminated. Mar 26 19:27:03 localhost pppd[10353]: Connect time 0.1 minutes. Mar 26 19:27:03 localhost pppd[10353]: Sent 1302 bytes, received 1196 bytes. Mar 26 19:27:03 localhost nm-dispatcher: req:5 'down' [ppp0]: new request (1 scripts) Mar 26 19:27:03 localhost nm-dispatcher: req:5 'down' [ppp0]: start running ordered scripts... Mar 26 19:27:03 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 1 / phase 'dead' Mar 26 19:27:03 localhost NetworkManager[2071]: Script /etc/ppp/ip-down finished (pid 10523), status = 0x0 Mar 26 19:27:03 localhost NetworkManager[2071]: Script /etc/ppp/ipv6-down finished (pid 10527), status = 0x0 Mar 26 19:27:03 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_exit_notify): cleaning up Mar 26 19:27:03 localhost pppd[10353]: Script /etc/ppp/ip-down finished (pid 10523), status = 0x0 Mar 26 19:27:03 localhost NetworkManager[2071]: <info> [1522092423.7625] devices removed (path: /sys/devices/virtual/net/ppp0, iface: ppp0) Mar 26 19:27:03 localhost pppd[10353]: Script /etc/ppp/ipv6-down finished (pid 10527), status = 0x0 Mar 26 19:27:03 localhost pppd[10353]: Exit. Mar 26 19:27:17 localhost NetworkManager[2071]: <info> [1522092437.1293] ppp-manager: starting PPP connection Mar 26 19:27:17 localhost NetworkManager[2071]: <info> [1522092437.1344] ppp-manager: pppd started with pid 10576 Mar 26 19:27:17 localhost pppd[10576]: Plugin /usr/lib/pppd/2.4.7/nm-pppd-plugin.so loaded. Mar 26 19:27:17 localhost NetworkManager[2071]: Plugin /usr/lib/pppd/2.4.7/nm-pppd-plugin.so loaded. Mar 26 19:27:17 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (plugin_init): initializing Mar 26 19:27:17 localhost pppd[10576]: pppd 2.4.7 started by root, uid 0 Mar 26 19:27:17 localhost pppd[10576]: Device ttyACM0 is locked by pid 10520 Mar 26 19:27:17 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 3 / phase 'serial connection' Mar 26 19:27:17 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 1 / phase 'dead' Mar 26 19:27:17 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_exit_notify): cleaning up Mar 26 19:27:17 localhost pppd[10576]: Exit. Mar 26 19:27:17 localhost NetworkManager[2071]: <warn> [1522092437.1605] ppp-manager: pppd pid 10576 exited with error: Serial port lock failed Mar 26 19:27:28 localhost NetworkManager[2071]: <info> [1522092448.3542] ppp-manager: starting PPP connection Mar 26 19:27:28 localhost NetworkManager[2071]: <info> [1522092448.3592] ppp-manager: pppd started with pid 10589 Mar 26 19:27:28 localhost pppd[10589]: Plugin /usr/lib/pppd/2.4.7/nm-pppd-plugin.so loaded. Mar 26 19:27:28 localhost NetworkManager[2071]: Plugin /usr/lib/pppd/2.4.7/nm-pppd-plugin.so loaded. Mar 26 19:27:28 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (plugin_init): initializing Mar 26 19:27:28 localhost pppd[10589]: pppd 2.4.7 started by root, uid 0 Mar 26 19:27:28 localhost pppd[10589]: Device ttyACM0 is locked by pid 10520 Mar 26 19:27:28 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 3 / phase 'serial connection' Mar 26 19:27:28 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 1 / phase 'dead' Mar 26 19:27:28 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_exit_notify): cleaning up Mar 26 19:27:28 localhost pppd[10589]: Exit. Mar 26 19:27:28 localhost NetworkManager[2071]: <warn> [1522092448.3865] ppp-manager: pppd pid 10589 exited with error: Serial port lock failed Mar 26 19:27:39 localhost NetworkManager[2071]: <info> [1522092459.7109] ppp-manager: starting PPP connection Mar 26 19:27:39 localhost NetworkManager[2071]: <info> [1522092459.7159] ppp-manager: pppd started with pid 10592 Mar 26 19:27:39 localhost pppd[10592]: Plugin /usr/lib/pppd/2.4.7/nm-pppd-plugin.so loaded. Mar 26 19:27:39 localhost NetworkManager[2071]: Plugin /usr/lib/pppd/2.4.7/nm-pppd-plugin.so loaded. Mar 26 19:27:39 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (plugin_init): initializing Mar 26 19:27:39 localhost pppd[10592]: pppd 2.4.7 started by root, uid 0 Mar 26 19:27:39 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 3 / phase 'serial connection' Mar 26 19:27:39 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_phasechange): status 1 / phase 'dead' Mar 26 19:27:39 localhost NetworkManager[2071]: nm-pppd-plugin-Message: nm-ppp-plugin: (nm_exit_notify): cleaning up Mar 26 19:27:39 localhost NetworkManager[2071]: <warn> [1522092459.7426] ppp-manager: pppd pid 10592 exited with error: Serial port lock failed Mar 26 19:27:39 localhost pppd[10592]: Device ttyACM0 is locked by pid 10520 Mar 26 19:27:39 localhost pppd[10592]: Exit. Mar 26 19:28:00 localhost NetworkManager[2071]: <warn> [1522092480.2188] ppp-manager: pppd timed out or didn't initialize our dbus module I am using nmcli through NetworkManager. I have seen other questions where people believe that the device is not supplying enough power to the USB. I still see the device in lsusb when it's offline though.

lsusb Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 002: ID 0424:5744 Standard Microsystems Corp. Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 005: ID 0424:2740 Standard Microsystems Corp. Bus 001 Device 004: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port Bus 001 Device 003: ID 1bc7:0036 Telit Wireless Solutions Bus 001 Device 002: ID 0424:2744 Standard Microsystems Corp. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

I have tried adding noipdefault to the options file but that didn't seem to work either.

I am at a total loss and any help debugging would be great.

Solution

I figured out the answer. The problem was that Verizon will cut a connection if it receives 10 invalid packets in a span of 2 minutes. The problem was that I wasn't NATing packets properly since I was also using this as a router. The packets being sent out from the bridged lan were being sent to verizon with a source IP of 192.168.123.XXX. Verizon (rightly so) decided that these packets were invalid and would shut off the connection. The solution was to simply add this Iptables rule:

iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE 

Comments

[Chirag Chhuchha]

This one worked but I also had to hit sudo ufw disable command in order to disable the firewall but thanks for the answer @zib323