Oneplus 8T phone connects, but no internet

[ffxxcad]

Files:
amf_log.txt
gNB_log.txt
gNB_mac.zip
gNB_ngap.zip

Setup:

• Ettus USRP B210
• National Instruments CDA 2990
• Oneplus 8T (European version)
• Gialer Programable Sim Card
• Open5GS Core

The gNB, amf, and upf configuration files are identical to the ones found here.

Issue:
Phone appears to be authenticated by the core but does not get a PDU Session and consequently does not have internet. We have tried these steps here without success.

Any thoughts? Thanks in advance.

[brendan-mcauliffe]

Hi @ffxxcad,

Typically, when the phone sees the network but isn't assigned a PDU, there is some misconfiguration between the core and the phone. I would check the following:

• Check that the APN configuration is exactly the same between the core and phone, also make sure it is set to IPv4 only.
• Make sure that VoLTE/ VoNR is disabled.

If this issue continues, please send the logs and pcaps for the latest test.

[ffxxcad]

Thanks for your reply. I double checked the APN in the core and the phone; both match. I also made sure that it was set to IPv4 only. VoLTE is disabled as well.

Logs from latest test:
amf_log.txt
gNB_log.txt
UE_radio_log.txt
gNB_mac.zip
gNB_ngap.zip

Screenshots:
Phone settings:

Open5GS Subscriber Information:

[herlesupreeth]

I see in your APN setting on the phone that APN type is set to ims rather it should be set to default

[ffxxcad]

@herlesupreeth I changed the APN type to default and saved the access point. Upon opening the Access point again I noticed that APN type has been reset to ims, leading me to believe that ims is the default parameter.

[herlesupreeth]

I have seen this behavior when the phone has a specific APN configuration baked into the OS which gets loaded as soon as you insert a SIM of particular PLMN. You can try the following method

Method 1:

1. Go to APN settings, then from the menu select --> "Reset APN to default"
2. The above will re-populate the APN stored in the OS for a PLMN
3. Add a new APN (srsapn with APN type as default)
4. Delete all other APN and restart the phone
5. Then, give it a try.

Method 2:

1. Same as above (i.e. reset APN to default, add new APN and delete all others)
2. For the srsapn, set the APN type as default,ims,ia
3. Then, give it a try

If both the method fails, then most probably you would have to root your phone and change the APN XML file in the OS.

[ffxxcad]

@herlesupreeth, thank you so much!

Method 1 helped the phone establish a PDU session, and in turn, an IP address (which previously did not work). However, the phone still did not have internet but could ping and iperf back and forth to the gNB.

Internet connection was established by re-running the commands listed under the "Adding a route for the UE to have WAN connectivity" section of the Open5GS quickstart guide.

Both iperf and internet connection is now working on the phone. Thanks again!