The phone cannot find the network

[Guo-arch1017]

Issue Description

I successfully started gnb but my phone cannot find the network

Setup Details

Ubuntu 24.04
Usrp X310
RF front-end: Vert 2450
Ue: Samsung S23

Expected Behavior

The mobile phone can successfully log into the Internet

Actual Behaviour

my phone cannot find the network

My gnb.yaml

My Terminal output

[pgawlowicz]

Could you share your gnb logs?

[Guo-arch1017]

Could you share your gnb logs?
This is my log
gnb.log

[Guo-arch1017]

I would like to ask if the transmitting power is too low?

ru_metrics
| ------------------- TX ------------------ | ------------------- RX ------------------ |
| Avg. power | Peak power | PAPR | Clipping | Avg. power | Peak power | PAPR | Clipping |
| -24.4 | -4.4 | 20.0 | 0.0e+00 | nan | -379.3 | nan | nan |

[pgawlowicz]

could you pull the newest code base and try again?

[Guo-arch1017]

could you pull the newest code base and try again?

After I reinstalled it's still the same

[Guo-arch1017]

I use a spectrum analyzer with 30db attenuation

[Guo-arch1017]

I updated UHD to the latest version and reinstalled srsRAN still the same

[pgawlowicz]

Did you follow this tutorial?
https://docs.srsran.com/projects/project/en/latest/tutorials/source/cotsUE/source/index.html

Which SIM card do you use?

[Guo-arch1017]

Did you follow this tutorial? https://docs.srsran.com/projects/project/en/latest/tutorials/source/cotsUE/source/index.html

Which SIM card do you use?
I switched to an ASUS phone and was able to connect to the 5G network, but I could only upload but not download, so I still couldn’t access the Internet.

[pgawlowicz]

Did you enable IP forwarding in the host running Open5gs?

sudo sysctl -w net.ipv4.ip_forward=1
sudo iptables -t nat -A POSTROUTING -o <IFNAME> -j MASQUERADE

Where is the name of the interface connected to the internet.

[Guo-arch1017]

Did you enable IP forwarding in the host running Open5gs?

sudo sysctl -w net.ipv4.ip_forward=1
sudo iptables -t nat -A POSTROUTING -o <IFNAME> -j MASQUERADE

Where is the name of the interface connected to the internet.

Do I need to type these instructions if I use docker open5gc?

[pgawlowicz]

no, on the hostmachine

[Guo-arch1017]

no, on the hostmachine

Do you mean that I don’t need to type these two instructions when using docker open5gc?

[pgawlowicz]

you have to run those two commands on the PC running docker container.

[Guo-arch1017]

you have to run those two commands on the PC running docker container.

Thanks, I'll try it

[Guo-arch1017]

you have to run those two commands on the PC running docker container.
sudo ip ro add 10.45.0.0/16 via 10.53.1.2
I enter the command to access the Internet.
I can use Google Chrome to search the web very quickly, but the bottom of the browser will show that you are offline. Please turn on wifi or mobile data, and you cannot click to enter the web page or use Youtube.

My phone is searching for mobile networks and cannot find any network, but I can use the 5G network and browse web pages, but I cannot click on them.

[Guo-arch1017]

you have to run those two commands on the PC running docker container.
sudo ip ro add 10.45.0.0/16 via 10.53.1.2
I enter the command to access the Internet.
I can use Google Chrome to search the web very quickly, but the bottom of the browser will show that you are offline. Please turn on wifi or mobile data, and you cannot click to enter the web page or use Youtube.

My phone is searching for mobile networks and cannot find any network, but I can use the 5G network and browse web pages, but I cannot click on them.

However, the network currently displays srsRAN

[pgawlowicz]

could you share your config and logs?

[Guo-arch1017]

could you share your config and logs?

gnb.zip

[Guo-arch1017]

could you share your config and logs?

gnb.zip

[pgawlowicz]

could you share also ngap pcap?

[Guo-arch1017]

could you share also ngap pcap?

ngappacap.zip

[pgawlowicz]

the UE connects correctly, could you check if you can ping 8.8.8.8 from open5gs docker container?

[Guo-arch1017]

the UE connects correctly, could you check if you can ping 8.8.8.8 from open5gs docker container?

If I set up automatic DNS on my phone, I still can't click on pages, but I can use the Facebook app
But you can’t use facebook on the web board
But not find mobile phone provider and cannot use line to send messages, but you can use FB messenger can send messages, make phone calls, or video chat

[pgawlowicz]

can you ping www.google.com from the open5gs container?

[Guo-arch1017]

can you ping www.google.com from the open5gs container?

ok

[Guo-arch1017]

你可以ping www.google.com從 open5gs 容器中嗎？

I'm wondering if it's because my phone can't find any telecommunications network

[Guo-arch1017]

can you ping www.google.com from the open5gs container?

I also need to enable roaming to use the 5G network. Is this one of the reasons?

[Guo-arch1017]

UE 連線正確，您可以檢查是否可以ping 8.8.8.8從 open5gs docker 容器連接嗎？

After I checked today, I found that it is not possible to browse the web using a browser, but I can use Facebook, IG, and Messenger、Google Meet apps.

[pgawlowicz]

@Guo-arch1017 Any update on this issue?
seems that sth is wrong with DNS. Could you sniff packets between the core network and internet?

[Guo-arch1017]

@Guo-arch1017 Any update on this issue? seems that sth is wrong with DNS. Could you sniff packets between the core network and internet?

I switched to a 5G router and the situation is still the same. I am wondering if this is the problem?

External Clock
A Leo Bodnar GPS reference clock was used as the USRP clock source for this set-up.

The use of an external clock is not essential, but it mitigates possible errors occurring as result of inaccuracies in the internal clock of the RF front-end being used. The issue comes from the CFOs and timings tolerated by 5G handsets - the onboard clocks within SDRs are not always accurate enough to operate within the limits allowed by the handsets. Using an external clock, which is much more accurate than an SDR onboard clock, reduces the likelihood that a COTS UE will be unable to see/ connect to the network due to synchronization issues.

[pgawlowicz]

It seems that the radio link already works correctly. There is probably some issue with core network settings (DNS or routing).

[Guo-arch1017]

It seems that the radio link already works correctly. There is probably some issue with core network settings (DNS or routing).

How can I check the route and DNS? I've already provided all the relevant data to you, and no issues were encountered.