[rrc] [error] Cell selection failure, no suitable or acceptable cell found

[Nawi98]

Hi @aligungr hope u're doing good I am using open5gs(running on an Ubuntu 20.04 virtual machine) and UERANSIM(running on my Raspberry PI 8gb B model) to run my project.

My open5gs deployment is based on https://bitbucket.org/infinitydon/open5gs-5gcore-ueransim-iot-docker-compose/src/master/ and my UERANSIM one on ur Wiki. I ran my docker-compose up command to ensure my services were running and they're were...

For open5gs the changes I made are: 1.in the amf.yaml, the oai-gnb.yaml and the oai-ue.yaml : PLMN(mcc=001,mnc=01) 2.in the oai-gnb.yaml file : gnbSearchList(172.21.0.200) binding to my Raspberry address 3.in the the oai-gnb.yaml file : -linkIp , ngapIp and gtpIp that bind to my Raspberry address : 172.21.0.200 -amfConf: addresses : 172.21.0.104 (my amf address) I also created via the webUI interface my first subscriber(see the 2 pics below) : For the UERANSIM here are the changes I made in the open5gs-ue0.yaml and open5gs-gnb0.yaml :

After doing all these configs here is the outpout: May u tell me please where I am mistaken? Cheers.

[Nawi98]

Hi @aligungr here is also my docker-compose.yaml (I think the error is occuring due to the UERANSIM and gNB IP adresses that I forgot to change). If I'm wrong please correct me... Else,since my UE and gNB both are running on my Raspberry what addresses should I enter?I am a little confused...

[aligungr]

@Nawi98

Looks like SCTP connection cannot be established according to gNodeB logs. Please double check your NGAP IP addresses.

[Nawi98]

@aligungr well firstly I commented the UE and the gnb configs in the docker-compose.yaml of my core VM.

So that the only UE and gnb that will be taken into account are those running on my Raspberry PI.

Secondly I double checked the NGAP IP as u adviced me (172.21.0.200 : my eth0 raspberry PI interface) but ran into the same issue.

Regards.

[Mariakhanmm92]

@Nawi98 were you able to resolve this issue? I am facing the same error currently, while connecting UERANSIM with Amarisoft’ Callbox 5GC. The configuration files are almost same as yours. I am unable to figure out the problem. Could you please assist? Thanks in advance!

[Mariakhanmm92]

Hello @aligungr! Hope you are doing well. Since this issue is already open therefore I am adding my issue here.

I am using Amarisoft 5GC with UERANSIM and facing the same error as mentioned by Mr. @Nawi98 .

The configuration at Amarisoft 5GC side is ; gtp_addr="192.168.1.134" (the IP address of the Ethernet interface of Callbox - bind address for GTP-U) ngap_bind_addr="192.168.1.134:38412"

The configuration at UERANSIM side is; linkIp, npapIp, gtpIp= "192.168.1.16" (IP address of the gNB, the ethernet interface of UERANSIM) amfConfig="192.168.1.134:38412" (the IP address of the Ethernet interface of Callbox)

I run 5GC first, then gNB and then UE. I captured the sctp traffic at gNB's interface and found out that no response is received from 5GC at this interface. There are only SCTP INIT packets with source (gNB) IP and port: 192.168.1.16:47527 and destination (5GC) IP & port: 192.168.1.134:38412.

Could you please suggest something to resolve this error?

Thanks and kind regards, Maria Khan

[aligungr]

Hi @Mariakhanmm92

There are lot's of possible causes, perhaps some firewall blocking the SCTP messaging, for example.

I think please try to check SCTP connectivity between two machines using this tool. Hopefully this could be the first diagnostics.

Best regards

[Mariakhanmm92]

Hello @aligungr , Thanks for your prompt feedback. As per your suggestion, i check the firewall and SCTP connectivity as well. Firewall is not configured at both sides, and there is SCTP connectivity between both machines. However, the issue is still persistent. I am receiving same error.

[aligungr]

@Mariakhanmm92 You can try this as a next step:

• First start wireshark in two of the machines.
• Then run the core network and then the gNodeB.
• Then make sure by 2 wireshark instances, that gNodeB sends SCTP init message to the core's machine, and core's machine receives the same SCTP init from the gNodeB's machine.

I'm pausing here for now

[Mariakhanmm92]

Hi @aligungr, Thanks for your assistance. The problem was with the configurations at the 5GC.cfg file. Now the SCTP/NGAP connections between the 5GC and gNodeB is successfully established.

Thanks and BR, Maria