Cant I send SMS while using 3G dongle as WWAN?

Hello guys, Im trying to send SMS with my 3G dongle that I'm currently using as WWAN.

I notice I get a message about "Resource temporarily unavailable" and I'm able to send it when I turn down the 3G interface.

So SMS is working, data is working, but I guess i can't use both?

Can someone confirm or deny this please.

Thanks a lot

If the 3G dongle uses PPP protocol, then the data is flowing through the same serial port that you would send an SMS through. So this is indeed impossible for 3G dongles that have only one virtual serial port and use the PPP protocol.


  • See if the dongle also supports some other protocol, e.g. NCM or MBIM;
  • See if there is a second serial port that also accepts AT commands so that you can send SMS through it.

thanks patrakov, i will try your suggestions!

im using UMTS/GPRS/EV-DO Protocol btw, but i guess the problem would be the same, probably, it makes sense that when the onle "channel" (serial) is busy, i cant do another thing

A bit of confusing terminology here, and possibly some misunderstanding.

The dongle of course uses the UMTS/GPRS/EV-DO protocol when communicating with the network. The question here is how the dongle communicates with your router. Valid choices here (outside of the OpenWRT world) are PPP, MBIM, and NCM. Maybe others exist. Dongles often support more than one protocol and treat PPP as legacy.

OpenWRT has the "UMTS/GPRS/EV-DO" name assigned, confusingly, to the legacy PPP-based way of communication with the dongle. If the dongle supports anything else, please use that other protocol.

E.g., if the dongle supports NCM, install luci-app-ncm, install the needed kmods, and connect. And use SMS while connected.


great info man, thanks for clarifying it
i will definitely check and try that.

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