R412M with KPN SIM fails eGPRS roaming in the UK

SARA AFF
1

We have here in the UK a KPN Dutch SIM which works fine when roaming in an Insys GPRS router. However when driving the SARA R412M board from one of our numerous Raspberry Pis it attaches and gets an IPv4 address, but then pppd 2.4.7 complains as follows:

Jun 24 12:01:44 stretchypi pppd[22430]: Serial connection established.
Jun 24 12:01:44 stretchypi pppd[22430]: using channel 46
Jun 24 12:01:44 stretchypi pppd[22430]: Using interface ppp0
Jun 24 12:01:44 stretchypi pppd[22430]: Connect: ppp0 <--> /dev/ttyACM0
Jun 24 12:01:45 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:01:48 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:01:51 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:01:54 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:01:57 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:02:00 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:02:03 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:02:06 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:02:09 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:02:12 stretchypi pppd[22430]: sent [LCP ConfReq id=0xa <asyncmap 0x0> <magic 0x765cd48> <pcomp> <accomp>]
Jun 24 12:02:15 stretchypi pppd[22430]: LCP: timeout sending Config-Requests
Jun 24 12:02:15 stretchypi pppd[22430]: Connection terminated.
Jun 24 12:02:16 stretchypi pppd[22430]: Modem hangup

I’m not a cellular comms expert, and may easily have set things up wrongly! Can anybody suggest what might be going wrong?

FYI - We force eGPRS mode with “AT+URAT=9”, but a subsequent “AT+URAT?” returns “ERROR”. Despite that things (mostly) seem to work as expected.

Jim

2

In case it proves of some use to somebody else we eventually managed to get PPP working by wiring up a direct USB connection to the R412 AFF as per these instructions for the R410:

https://support.sodaq.com/sodaq-one/sodaq-sara-r410m/#firmware_r4xx_update