The gNB Sim tool simulates gNodeB and UE by generating and processing NAS and NGAP messages for the configured UEs and call flows. The tool currently supports simulation profiles for the following procedures,
UE initiated PDU Session Establishment
UE Initiated De-registration.
It is also capable to generate and send user data packets (ICMP echo request) and process down-link user data (ICMP echo response) over the established data plane path (N3 Tunnel).
Configure gNB Simulator
The config file for GNBSIM can be found at <repo dir>/config/gnbsim.yaml
Note: The configuration has following major fields (Read the comments in the config file for more details)
gnbs: List of gNB’s to be simulated. Each item in the list holds configuration specific to a gNB.
profiles: List of test/simulation profiles. Each item in the list holds configuration specific to a profile.
Enable or disable a specific profile using the enable field.
Note: Currently following profiles are supported
register: Registration procedure
pdusessest (Default): Registration + UE initiated PDU Session Establishment + User Data packets
deregister: Registration + UE initiated PDU Session Establishment + User Data packets + Deregister
Build gNB Simulator
To modify gNB Sim within a container run
$ kubectl exec -it gnbsim-0 -n omec bash
Make required changes and run
$ go build
To modify gNB Sim and build a new docker image
$ cd <repo dir> $ make docker-build
Use newly created image in the AIAB cluster run,
$ cd <aiab repo dir> $ make reset-5g-test
Modify the override file (ransim-values.yaml) to add the new image name
$ make 5gc
Run gNB Sim
Enter into the gNB Sim pod by running$ kubectl exec -it gnbsim-0 -n omec bash
After entering the pod run,$ ./gnbsim
Note: By default, the gNB Sim reads the configuration from /free5gc/config/gnb.conf file. To provide a different configuration file, use the below command$ ./gnbsim --cfg config/gnbsim.yaml