LTE NB-IoT DNS



  • Hi,

    I just managed to get the FIPY connected to our internal test network using the recently released NB-IoT firmware from Sequans. However I'm having some issues with getting the DNS information from the network propagated to the FIPY modem. I discovered this when socket.getaddrinfo('www.google.com', 80) was returning nonsense IPs. So I digged a bit further and found this:

    lte.send_at_cmd('AT+CGCONTRDP')
    '\r\n+CGCONTRDP: 1,5,"internet.xxxx.xx.mncXXX.mccXXX.gprs","10.41.136.10.255.255.255.255","","","","",""\r\n\r\nOK\r\n'

    Refering to the Sequans AT manual, the empty parameters should contain gateway, primary and secondary dns IP addresses. So basically there is no DNS specified and all hostname lookups fails. Socket communication using IP addresses works fine.



  • @aris Actually in our case the DNS problem was caused by Sequans using EPCO in their NB-IOT firmware. Once we added support for EPCO in our network we got the DNS server info populated.



  • I get the same problem with the FiPy and our internal NB-IoT network. The DNS seems to be broken for NB-IoT. Are there any plans to fix the problem, or do we have to keep working with fixed IPs?

    Related issue: https://github.com/pycom/pycom-libraries/issues/57



  • @jcaron
    It worked fine using the Cat M1 firmware. It's part of the PDN Connectivity Request (PCO) sent from UE to network. Not sure whether PCO or ePCO is used when requesting the IP configuration. The UE must request a DNS when establishing a connection on the default bearer, and the network will respond with a Activate Default EPS Bearer Request which includes UE IP, DNS etc.



  • @redferne Are you sure your test network is indeed sending that information to the node?


 

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