How to arrange for SIM1 and SIM2 to connect to different providers when roaming in Europe

Here is a typical scenario. I have 2 SIMs from same provider Proximus
in Belgium, and, to roam in France, I have to keep the settings from
my provider in Belgium such as APN, username, password, etc… I can
connect to and register with several providers in France, but I limit
myself to comparing the two best ones SFR and Bouyges which seem to
have best deals with Proximus. Dependent on location, one of these two
providers sometimes has much better performance than the other one.

I would like to arrange for SIM1 to only connect to SFR and for SIM2
to only connect to Bouyges. Then it is easy to consistently check
which one is best at any time and any location, and to choose that one
by switching to that SIM.

But how can I do this?

I guess I can lock each SIM to a tower from one provider, but, when on
the go, that does not seem like a good idea.

On a GL-X750 running standard OpenWRT, I managed to choose operator by

option plmn ‘208010’ # SFR
option plmn ‘208020’ # Bouyges

on mobile interface in network file.

But that is a bit tedious to change as it requires ssh access.

On the GL-XE3000 this may work as well, I wil soon try, but, having
the luxury to host 2 SIMs, I hope maybe there is a smoother way
… perhaps as follows in glmodem file:

always choose SFR

config network ‘network_sim1’
option plmn ‘208010’

always choose Bouyges

config network ‘network_sim2’
option plmn ‘208020’

Would this work?

Or is there another working recommended solution?

Maybe using AT commands?

1 Like

You need to try translating the option plmn to AT commands:


@admon :

Thanks a lot for this help! I had searched for but did not find mcc mnc and plmn in Quectel AT manual … :dotted_line_face:

Are you saying ‘option plmn some-plmn’ config will not work on network or modem level and AT is needed?

The CPOL looks easy, and, I guess, does not write to any SIM. And, I guess, CSIM commands are needed to write to SIM. These look a bit daunting but I think I get it.

The example given


uses e000 as Access Technology Identifier for first PLMN but I guess I will need LTE+5G 7800. Then it uses different 0e00 as Access Technology Identifier or second PLMN (is that a typo?) but I guess I will need LTE+5G 7800 there too. Right?

Also, length 510 looks big (I suppose it erases until end of folder, hopefully not too far), perhaps 40 works as well (if no one ever wrote anything longer). Right?