USB Serial Modem LCP after ~60 minutes

I have an Alcatel Onetouch X500 USB serial modem connected to a RasPi 2 Model B running Ubuntu 16.04.2 LTS.

I use wvdial for connecting to the network (config follows):

Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Modem Type = USB Modem
Phone = 99**1#
ISDN = 0
Username = " "
Password = " "
Init1 = ATZ
Init3 = AT+CGDCONT=1,“IP”,“hologram”
Modem = /dev/ttyUSB3
Baud = 9600
Stupid Mode = on
Auto DNS = 0
Dial Command = ATDT
Carrier Check = yes
Auto Reconnect = on```

I have been using this as an emergency ssh portal in the event of my primary system going down for a few weeks without issue. Recently the modem has been disconnecting from the T-Mobile tower regularly at ~60 minutes. I wrote a service to check for a connection and reconnect if it’s disconnected. Below is a section of the logs:

``Apr 12 20:14:30 raspi pppd[22801]: Connect time 60.1 minutes.
Apr 12 20:15:01 raspi monusbmodem[22774]: WAN Link Up
Apr 12 21:14:42 raspi pppd[23878]: Connect time 60.1 minutes.
Apr 12 21:15:18 raspi monusbmodem[22774]: WAN Link Up
Apr 12 22:14:55 raspi pppd[24973]: Connect time 60.1 minutes.
Apr 12 22:15:35 raspi monusbmodem[22774]: WAN Link Up
Apr 12 23:15:09 raspi pppd[26031]: Connect time 60.1 minutes.
Apr 12 23:15:52 raspi monusbmodem[22774]: WAN Link Up
Apr 13 00:15:21 raspi pppd[27118]: Connect time 60.1 minutes.
Apr 13 00:16:09 raspi monusbmodem[22774]: WAN Link Up
Apr 13 01:15:34 raspi pppd[28470]: Connect time 60.1 minutes.
Apr 13 01:16:26 raspi monusbmodem[22774]: WAN Link Up
Apr 13 02:15:47 raspi pppd[29560]: Connect time 60.1 minutes.
Apr 13 02:16:43 raspi monusbmodem[22774]: WAN Link Up
Apr 13 03:16:00 raspi pppd[30939]: Connect time 60.1 minutes.
Apr 13 03:17:00 raspi monusbmodem[22774]: WAN Link Up
Apr 13 04:16:12 raspi pppd[32024]: Connect time 60.1 minutes.
Apr 13 04:17:16 raspi monusbmodem[22774]: WAN Link Up
Apr 13 05:16:27 raspi pppd[655]: Connect time 60.1 minutes.
Apr 13 05:17:33 raspi monusbmodem[22774]: WAN Link Up
Apr 13 06:16:40 raspi pppd[1804]: Connect time 60.1 minutes.
Apr 13 06:17:50 raspi monusbmodem[22774]: WAN Link Up
Apr 13 07:16:55 raspi pppd[3168]: Connect time 60.1 minutes.
Apr 13 07:17:17 raspi monusbmodem[22774]: WAN Link Up
Apr 13 08:17:07 raspi pppd[4345]: Connect time 60.1 minutes.
Apr 13 08:17:34 raspi monusbmodem[22774]: WAN Link Up
Apr 13 09:17:22 raspi pppd[5489]: Connect time 60.1 minutes.
Apr 13 09:17:51 raspi monusbmodem[22774]: WAN Link Up
Apr 13 10:17:35 raspi pppd[6578]: Connect time 60.1 minutes.
Apr 13 10:18:08 raspi monusbmodem[22774]: WAN Link Up


Apr 12 16:42:48 raspi pppd[17965]: rcvd [LCP TermReq id=0x37]
Apr 12 16:42:48 raspi pppd[17965]: LCP terminated by peer
Apr 12 16:42:48 raspi pppd[17965]: Connect time 60.0 minutes.
``

It’s a little less regular in older logs but it’s always right around 60 minutes.

Is this something I need to configure on my side?
Is it an idle timeout from hologram or T-Mobile?

I’m not sure if this is expected behavior as it wasn’t happening when I started a few weeks ago but is now.

Thanks!

Nothing wrong on your side. After 60 minutes of inactivity, the connection will be closed. This is on the carrier side.

So my service is probably the best approach then? That works for me, and good to know, thanks!