The target Architectural diagram has two parts. (a) Virtualized 5G Core¹ and (b) gNB docker. This tutorial is about how to create gNB docker. We have used Intel Core i7 systems along with Ettus B210 with Ubuntu 20.04.LTS and we suggest use of same OS.

We have used the following Tutorial to install docker engine. Interested readers may go through the given tutorial to avoid sudo while using docker along with multiple other useful things. ```

sudo apt update

sudo apt install apt-transport-https ca-certificates curl software-properties-common

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu focal stable"

apt-cache policy docker-ce

sudo apt install docker-ce

sudo systemctl status docker
```

```
git clone https://github.com/subhrendu1987/oai-gnodeb
```

```	
cd oai-gnb-docker_ubuntu20 
cat oai-gnb_20.tar.a? > oai-gnb_20.tar
sudo docker load --input oai-gnb_20.tar
sudo docker tag <Image-ID> oai-gnb:latest
```

1. ping test from GNB to AMF and AMF to GNB. If ping is not successfull, then try to debug
   1. Commands to be executed in gNB to enable packet forwarding from Core to the external network via the Core VM

      sudo sysctl net.ipv4.ip_forward=1
      sudo iptables -P FORWARD ACCEPT
      sudo ip route add 192.168.70.128/26 via <Bridge IP of Core VM>
      

   2. Check routing tables of GNB Docker, GNB Baremetal, Core VM, Core Baremetal
   3. For ease of operations use the Google sheet tool

```
sudo docker run -it \
        -v /dev:/dev \
        --privileged \
        -e USE_SA_TDD_MONO_B2XX='yes' \
        -e USE_B2XX='yes' \
        -e GNB_NAME='gNB-in-docker' \
        -e MCC='001' \
        -e MNC='01' \
        -e MNC_LENGTH=2 \
        -e TAC=1 \
        -e NSSAI_SST=1 \
        -e NSSAI_SD0=1 \
        -e AMF_IP_ADDRESS='172.21.16.136' \
        -e GNB_NGA_IF_NAME='eth0' \
        -e GNB_NGA_IP_ADDRESS='192.168.68.194' \
        -e GNB_NGU_IF_NAME='eth0' \
        -e GNB_NGU_IP_ADDRESS='192.168.68.194' \
        -e USE_ADDITIONAL_OPTIONS='--sa --continuous-tx --log_config.global_log_options level,nocolor,time,line_num,function' \
        --entrypoint "/bin/bash" \
        oai-gnb:latest \
        --name sa-b210-gnb \
        /bin/bash
```

Edit ci-scripts/yaml_files/sa_b200_gnb/docker-compose.yml and modify the following variables as per the core specification:

1. AMF_IP_ADDRESS
2. GNB_NGA_IP_ADDRESS
3. GNB_NGU_IP_ADDRESS
4. GNB_NGU_IP_ADDRESS
5. MCC
6. MNC

1. cd ci-scripts/yaml_files/sa_b200_gnb/; sudo docker compose -f docker-compose.yml up -d
2. Now Execute NR inside the container
   1. sudo docker attach sa-b210-gnb # Enter into the oai-gnb docker
   2. Inside docker
      1. bash bin/entrypoint.sh
      2. /opt/oai-gnb/bin/nr-softmodem -O /opt/oai-gnb/etc/gnb.conf $USE_ADDITIONAL_OPTIONS
   3. sudo docker compose -f ci-scripts/yaml_files/sa_b200_gnb/docker-compose.yml down files.

1. uhd_find_devices
2. ping test from GNB to AMF and AMF to GNB. If ping is not successfull, then try to debug
   1. Commands to be executed in Core-VM

      sudo sysctl net.ipv4.ip_forward=1
      sudo iptables -P FORWARD ACCEPT
      sudo ip route add 192.168.71.194 via <GNB IP>
      

   2. Check routing tables of GNB Docker, GNB Baremetal, Core VM, Core Baremetal
   3. To test/debug/understand the nr-softmodem configurations use /custom folder version of entrypoint.sh script and /custom/conf configuration

1. Install Astra streaming studio in the UE
2. Create a RTMP streaming service with it by tapping on the globe icon in right side pane. Use service name as RTMP and Profile name as oai-core
   • Server IP: 192.168.70.141:1935/live
   • Stream ID: test
   • Save it and start the service using the play button