5G SA UEs -- Looking for known good ones and help debugging connection issues

[lucasgonze]

Discussed in #15297

^{Originally posted by jblakley August 30, 2023}
We are building out our 5G test environment as an evolution of our current LTE network. We're on CBRS n48 for 5G. The AGW, gNB, and Orc8r are up, connected and enabled for 5G. I have tried to connect 2 different 5G UE with marginal success. Progress so far:

1. UE 1 -- Pixel 7 Pro. We've been using this already in our LTE network and it supports 5G SA on CBRS n48. Initially, it wouldn't even see our 5G network but, based on info from our gNB vendor (Sercomm), when I moved the network to PLMN 00101, it did see it and completes registration. However, after (reliably) ~10 seconds, the UE drops the connection. While the InitialContextSetupResponse comes from gNB to AMF, the NAS Registration Complete message from UE to AMF never arrives. AMF/MME log does say registration complete but the UE logs never go to CONNECTED. A potentially related thing -- when I scan in our lab, there are other networks using the 00101 PLMN -- one on band L2 and one on band L66. They are not ours but could be confusing our UE. At a dead end now, so any ideas on this?

2. UE 2 -- Oneplus 9 Pro. This model is known good for 5G SA on n48 but our two UEs of this type don't even see our network. Have tried both on the 00101 PLMN and our standard network PLMN. Although they were sold as unlocked, they may only be unlocked for T-Mobile, AT&T, and Verizon. Is there a reliable way to see whether they are locked such that they won't connect to a private network? Even better, any one know a way to carrier unlock them? Any other explanations for this behavior.

Happy to share additional info as needed.

Now to a more general question -- if I can't get any of these UEs to work, I'll have to find another. Has anyone found and connected to Magma a 5G SA smartphone UE on band n48 -- if so what type and how did you verify it was unlocked before you got it? If you've done it, just not on n48, please share that too!

@jordanvrtanoski

[Radula76]

We are using SA band78. iPhones need SUCI extensions, iPhone 13 and above on iOS17 (i think, to use PLMN 999/XX). Android (Samsung) like to have the IMS or Voice over PS enabled, even if the APN does not exist and it gets rejected.
We have used Siemens MUM-586 (the 583 didn't like 999 PLMN and could not see the network), Westermo 5G CPE, Mikrotik 5G CPE, Teltonika RUTX-50, Milesight 5G CPE, we are testing some new BTI devices as well.
Make sure that the device is configured to do APN IPv4, lots try IPv4v6. you can setup IPv6 but its a bit of work for the whole network to use IPv6. You can check what sessions the phone is trying with your N2/N3 pcap trace. check the APN(IP version), if its trying GUTI or IMSI attach, if its trying SUCI, if it tries a default APN and then an IMS APN.