How to activate 4G roaming on TL-MR6400

Installing and Using OpenWrt
1

Hi,

today I set up my new TL-MR6400 Ver 5.30 with OpenWRT 23.05

Everything is working fine. I also managed to get the 4G Modem up an running.

I´m based in Germany but work in Switzerland. So I have a swiss 4G SIM card with roaming.

But I did not manage to set Roming "on", so I can use this SIM also in Germany (40GB roaming Data in Contract included).
When I use a German SIM instead, the Router and the 4G works fine (in Germany)

I tried uqmi -d /dev/cdc-wdm0 --set-network-roaming any but it did not work.

I was not able to use an terminal to set AT commandy because the modem seems not to be USB connected so I can´t access it via serial terminal.

This is the output of some diagnostic:

root@OpenWrt:~# uqmi -d /dev/cdc-wdm0 --get-serving-system
{
        "registration": "registered",
        "plmn_mcc": 262,
        "plmn_mnc": 2,
        "plmn_description": "▒79l~▒▒.r\u0019",
        "roaming": true
}
root@OpenWrt:~# uqmi -d /dev/cdc-wdm0 --get-signal-info
{
        "type": "lte",
        "rssi": -72,
        "rsrq": -7,
        "rsrp": -101,
        "snr": 18.600000
}
root@OpenWrt:~# uqmi -d /dev/cdc-wdm0 --get-data-status
"connected"


root@OpenWrt:~# cat /etc/config/network
.
.
.
config interface 'Sunriseinternet'
        option proto 'qmi'
        option device '/dev/cdc-wdm0'
        option auth 'none'
        option pdptype 'ipv4'
        option apn 'internet'



ifconfig
wwan0     Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
          inet addr:10.57.38.38  P-t-P:10.57.38.38  Mask:255.255.255.252
          inet6 addr: fe80::bf4c:671d:bd39:593d/64 Scope:Link
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:2 errors:0 dropped:0 overruns:0 frame:0
          TX packets:7579 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:630 (630.0 B)  TX bytes:679441 (663.5 KiB)


ls -al /dev/ttyUSB*
ls: /dev/ttyUSB*: No such file or directory

I hope someone can help me to set up roaming so I can use this Router in my Camper on vacation.

Cheers

Udo

2

The output you provided shows that the modem is registered, connected, etc. in roaming.
What is the problem?

3

The Problem is = no Internet connection when I use the Swiss SIM in Germany.

When I use the German SIM (in Germany )it works.

No ping 8.8.8.8 from SSH Terminal, no running LuCI diagnostic, no WWW on PC-Client.

The Swiss SIM works fine in my Notebook (also roaming in Germany)

4

Please show the output of ifstatus Sunriseinternet once connected in roaming.

Have you tried connecting to another German network?

5

Hi AndrewZ,

thx for your help. Here is the output of ifstatus Sunriseinternet and ifstatus Sunriseinternet_4:

root@OpenWrt:~# ifstatus Sunriseinternet
{
        "up": true,
        "pending": false,
        "available": true,
        "autostart": true,
        "dynamic": false,
        "uptime": 596,
        "l3_device": "wwan0",
        "proto": "qmi",
        "updated": [
                "data"
        ],
        "metric": 0,
        "dns_metric": 0,
        "delegation": true,
        "ipv4-address": [

        ],
        "ipv6-address": [

        ],
        "ipv6-prefix": [

        ],
        "ipv6-prefix-assignment": [

        ],
        "route": [

        ],
        "dns-server": [

        ],
        "dns-search": [

        ],
        "neighbors": [

        ],
        "inactive": {
                "ipv4-address": [

                ],
                "ipv6-address": [

                ],
                "route": [

                ],
                "dns-server": [

                ],
                "dns-search": [

                ],
                "neighbors": [

                ]
        },
        "data": {
                "cid_4": "1",
                "pdh_4": "-2046364336"
        }
}
root@OpenWrt:~# ifstatus Sunriseinternet_4
{
        "up": true,
        "pending": false,
        "available": true,
        "autostart": true,
        "dynamic": true,
        "uptime": 597,
        "l3_device": "wwan0",
        "proto": "dhcp",
        "device": "wwan0",
        "updated": [
                "addresses",
                "routes",
                "data"
        ],
        "metric": 0,
        "dns_metric": 0,
        "delegation": true,
        "ipv4-address": [
                {
                        "address": "10.85.135.154",
                        "mask": 30
                }
        ],
        "ipv6-address": [

        ],
        "ipv6-prefix": [

        ],
        "ipv6-prefix-assignment": [

        ],
        "route": [
                {
                        "target": "0.0.0.0",
                        "mask": 0,
                        "nexthop": "10.85.135.153",
                        "source": "10.85.135.154/32"
                }
        ],
        "dns-server": [
                "212.161.168.15",
                "212.161.168.14"
        ],
        "dns-search": [

        ],
        "neighbors": [

        ],
        "inactive": {
                "ipv4-address": [

                ],
                "ipv6-address": [

                ],
                "route": [

                ],
                "dns-server": [

                ],
                "dns-search": [

                ],
                "neighbors": [

                ]
        },
        "data": {
                "zone": "wan",
                "dhcpserver": "10.85.135.153",
                "hostname": "OpenWrt",
                "leasetime": 7200,
                "zone": "wan"
        }
}

How can I change the connected 4G network for testing?

6

All looks good to me. Can you run any DNS query on the router, like nslookup openwrt.org ?

You can use option plmn to select specific provider, see https://openwrt.org/docs/guide-user/network/wan/wwan/ltedongle#qmi_protocol_configuration_parameters

7 
root@OpenWrt:~# nslookup openwrt.org
;; connection timed out; no servers could be reached

OpenWRT

I discovered that every time, I receive only 630 B (2 Pkts.) on the 4G internet.

Is there an option to check the roaming setting? (roaming on/off)?

I will try to change the network and post an update.

8

You have roaming enabled and used, otherwise you wouldn't get an IP address.

Try disabling DHCP for QMI with option dhcp '0' and see if it will make any difference.

9

It is an roaming issue. I put the SIM back to my Windows Notebook and tried to connect to 4G. And I got the info that roaming is disabled. So I enabled roaming on the SIM card and then it worked on my Windows Notebook.

After this I put the SIM back in the router and now it works! I have an Internet connection. :slight_smile:

@AndrewZ many thanks for your support!

Cheers

Udo