The goal of this repository is to create a simplified Kubernetes 5G Core deployment based on the Open Air Interface (OAI) OPENAIR-CN-5G project (https://gitlab.eurecom.fr/oai/cn5g/oai-cn5g-fed/). Numerous modifications have been made, which are outlined below.

• HTTP2 is used on all Service Based Interfaces (SBIs). Relevant Configmaps with appropriate values are already set.
• Some custom images for the SMF and AMF are used
• To simplify things, multus is disabled
• Helper install and uninstall scripts are included, which deploy the helm charts in the correct order
• Charts which aren't using my custom builds are using version v1.3.0 of the images found in the rdefosseoai repo. One notable exception to this is the UPF/PGW, which is using v1.1.2.
• The tcpdump container is not used in this deployment. It has been commented out of the deployment files.

In addition to the 5G core, I've included a UERANSIM build that has some tools built into it (such as ping) to make its use easier. It also has some UE and gNodeB config files that are tailored to the OAI implementation (e.g. appropriate MNC, MCC, APN, keys, etc.). This image is based on the open source implementation found here: https://github.com/aligungr/UERANSIM. Using the manifest I've provided, you can deploy the UERANSIM client as a Pod in your cluster, for simplified communication to and from the 5G packet core.

1. Clone this repository

   git clone https://github.com/mitch-pan/oai-cn5g-simple.git

2. cd into the charts directory

   cd oai-cn5g-simple/charts

3. Ensure K8s connectivity

   Make sure you are connected to the Kubernetes cluster where you want your 5G core deployed (e.g. kubectl get nodes should show the nodes of your cluster)

4. Create the oai namespace

   kubectl create namespace oai

5. If this is your first time to deploy, its probably best to go slowly. Run each command below and troubleshoot any issues you see.

   helm install mysql mysql/ -n oai 
   helm install nrf oai-nrf/ -n oai 
   helm install udr oai-udr/ -n oai
   helm install udm oai-udm/ -n oai
   helm install ausf oai-ausf/ -n oai
   helm install amf oai-amf/ -n oai
   helm install smf oai-smf/ -n oai
   helm install upf oai-spgwu-tiny/ -n oai
   

   After these work you can use the install_all.sh script instead.

6. Deploy the UERANSIM pod

   Make sure you are not in the charts directory, but in the main repo directory where the ueransim.yaml manifest is located.
   
   kubectl apply -f ueransim.yaml

7. Excec into the UERANSIM pod

   kubectl exec --stdin --tty ueransim -- /bin/bash

8. Edit the oai-gnb.yaml config file.
   
   The MNC and MCC should be set appropriately. Verify the MCC is 208, the MNC should be 95. You will need to set the linkIP, ngapIp and gtpIp to the be eth0 interface IP of the UERANSIM Pod. See below for examples.
   

   json
   mcc: '208'          # Mobile Country Code value<br>
   mnc: '95'           # Mobile Network Code value (2 or 3 digits)
   

   $ kubectl get pod ueransim -o wide</code> <--- This will show your UERANSIM IP
   $ kubectl get pods -n oai</code> <--- This will show your your AMF IP
   
   Assuming my UERANSIM was on 192.168.0.228 and my AMF had the IP 192.168.18.136 my gnb config file would contain the following:
   

   linkIp: 192.168.0.228   # gNB's local IP address for Radio Link Simulation (Usually same with local IP)
   ngapIp: 192.168.0.228   # gNB's local IP address for N2 Interface (Usually same with local IP)
   gtpIp: 192.168.0.228    # gNB's local IP address for N3 Interface (Usually same with local IP)
   

   amfConfigs:
     - address: 192.168.18.136
       port: 38412
   

9. Edit the oai-ue.yaml config file.
   All the subscriber information can be found in the mysql values.yaml file, but I will summarize it below:
   
   Provisioned IMSIs:
   208950000000030 208950000000031 208950000000032 208950000000033 208950000000034

   The only field you should need to edit in the oai-ue.yaml file is the IP address of the gNodeB. Open the manifest file and set the gnbSearchList appropriately. If my UERANSIM was using IP address 192.168.0.128, my config would like like the following:

   # List of gNB IP addresses for Radio Link Simulation
   gnbSearchList:
   - 192.168.0.128
   

   Feel free to make copies of this manifest using the other IMSI values. This will allow you to attach multiple UEs at the same time if you desire to.

10. Attach gNodeB to AMF

    If we have done everything correctly, our gNodeB should connect without any issue. To attempt a connection to the AMF, run:
    
    ./build/nr-gnb -c config/oai-gnb.yaml
    
    If all goes well you should see something like:
    

    ./build/nr-gnb -c config/oai-gnb.yaml 
    UERANSIM v3.2.6
    [2022-03-10 20:48:24.802] [sctp] [info] Trying to establish SCTP connection... (192.168.18.136:38412)
    [2022-03-10 20:48:24.813] [sctp] [info] SCTP connection established (192.168.18.136:38412)
    [2022-03-10 20:48:24.813] [sctp] [debug] SCTP association setup ascId[79]
    [2022-03-10 20:48:24.813] [ngap] [debug] Sending NG Setup Request
    [2022-03-10 20:48:24.816] [ngap] [debug] NG Setup Response received
    [2022-03-10 20:48:24.816] [ngap] [info] NG Setup procedure is successful
    

11. UE Attach

    While the gNodeB is running, we'll execute the UE attach in a different tab/window. Use kubectl to connect to the pod.
    
    kubectl exec --stdin --tty ueransim -- /bin/bash
    
    Once in the Pod:
    
    cd UERANSIM
./build/nr-ue -c config/oai-ue.yaml
    
    If all goes well you should see something like the following:
    

    ./build/nr-ue -c config/oai-ue.yaml 
    UERANSIM v3.2.6
    [2022-03-10 21:44:01.005] [nas] [info] UE switches to state [MM-DEREGISTERED/PLMN-SEARCH]
    [2022-03-10 21:44:01.005] [rrc] [debug] New signal detected for cell[1], total [1] cells in coverage
    [2022-03-10 21:44:01.005] [nas] [info] Selected plmn[208/95]
    [2022-03-10 21:44:01.005] [rrc] [info] Selected cell plmn[208/95] tac[1] category[SUITABLE]
    [2022-03-10 21:44:01.005] [nas] [info] UE switches to state [MM-DEREGISTERED/PS]
    [2022-03-10 21:44:01.005] [nas] [info] UE switches to state [MM-DEREGISTERED/NORMAL-SERVICE]
    [2022-03-10 21:44:01.005] [nas] [debug] Initial registration required due to [MM-DEREG-NORMAL-SERVICE]
    [2022-03-10 21:44:01.005] [nas] [debug] UAC access attempt is allowed for identity[0], category[MO_sig]
    [2022-03-10 21:44:01.005] [nas] [debug] Sending Initial Registration
    [2022-03-10 21:44:01.006] [nas] [info] UE switches to state [MM-REGISTER-INITIATED]
    [2022-03-10 21:44:01.006] [rrc] [debug] Sending RRC Setup Request
    [2022-03-10 21:44:01.006] [rrc] [info] RRC connection established
    [2022-03-10 21:44:01.006] [rrc] [info] UE switches to state [RRC-CONNECTED]
    [2022-03-10 21:44:01.006] [nas] [info] UE switches to state [CM-CONNECTED]
    [2022-03-10 21:44:01.034] [nas] [debug] Authentication Request received
    [2022-03-10 21:44:01.037] [nas] [debug] Security Mode Command received
    [2022-03-10 21:44:01.038] [nas] [debug] Selected integrity[1] ciphering[1]
    [2022-03-10 21:44:01.044] [nas] [debug] Registration accept received
    [2022-03-10 21:44:01.044] [nas] [info] UE switches to state [MM-REGISTERED/NORMAL-SERVICE]
    [2022-03-10 21:44:01.044] [nas] [debug] Sending Registration Complete
    [2022-03-10 21:44:01.044] [nas] [info] Initial Registration is successful
    [2022-03-10 21:44:01.044] [nas] [debug] Sending PDU Session Establishment Request
    [2022-03-10 21:44:01.044] [nas] [debug] UAC access attempt is allowed for identity[0], category[MO_sig]
    [2022-03-10 21:44:01.274] [nas] [debug] PDU Session Establishment Accept received
    [2022-03-10 21:44:01.274] [nas] [info] PDU Session establishment is successful PSI[1]
    [2022-03-10 21:44:01.286] [app] [info] Connection setup for PDU session[1] is successful, TUN interface[uesimtun0, 12.1.1.129] is up.
    

    Congratulations! You just set up a 5G PDU session! To send traffic through the UE's tunnel interface, run ping with the -I argument. For example:
    
    ping -I uesimtun0 google.com
    
    Feel to explore the logs of the Pods, they have tons of information about the messaging back and forth, registration status, etc.

    For example, to see AMF logs, you could run the following (replacing the xyz with the appropriate suffix)
    

    kubectl logs oai-amf-xyz -n oai