NF Status

PLMN999/70

IMSI999700000000001

UE Pool10.45.0.0/16

Web UI:9999

AMF

SMF

UPF

NRF

AUSF

UDM

UDR

PCF

NSSF

BSF

5G Core Network FabricOpen5GS · Service-Based Architecture

Live

PLMN 999/70 UE Pool 10.45.0.0/16 updated —

Terminal — root@5gcore-lab

connecting… — — — — — —

Click to copy, then paste in the terminal (right-click or Ctrl+Shift+V). All read-only — no sudo needed; the web buttons run the root actions.

5G Protocol Observatory

Idle · Live NGAP · NAS · SBI · GTP-U decode and flow analysis

Activity Trend (last 60 updates)

FILTER: Packets: 0

At idle you'll see mostly GTP-U (continuous user data). To capture NGAP / NAS / PFCP / SBI signalling, press Start then trigger a Registration or PDU session in the Procedures tab — the live call flow streams in here.

#	Proto	Src	Dst	Len	Info

Messages: 0

gNB

AMF

SMF

UPF

AUSF

UDM

NRF

LEVEL: Lines: 0

Total: 0

IMSI	K	OPc	AMBR DL/UL	DNN	Slice

NF:

Network Function Control

N6 Traffic Impairment (UPF tunnel)

Delay (ms): Loss %:

Adds tc qdisc netem rules on ogstun interface. Useful for testing UE resilience, HARQ, TCP behaviour across the N6 link.

Quick Procedures

3GPP Procedure Player

Trigger real 5G procedures via UERANSIM nr-cli. Watch the Call Flow (Ladder) tab in another session to see the live sequence diagram.

SST: DNN:

nr-cli output

Pick a procedure above to see live output...

3GPP Procedure Reference

Initial Registration (TS 23.502 §4.2.2.2.2)

UE → gNB: RRC Setup
UE → AMF: Registration Request
AMF ↔ AUSF/UDM: Nausf_UEAuth, Nudm_SDM
AMF → UE: Authentication Req/Resp → Security Mode → Registration Accept

PDU Session Establishment (§4.3.2.2.1)

UE → AMF: PDU Session Est Request (NAS)
AMF → SMF: Nsmf_PDUSession_CreateSMContext
SMF ↔ UDM/PCF: SM Policy Association
SMF → UPF: N4 Session Establishment
SMF → AMF → gNB → UE: PDU Session Est Accept

Paging (§4.2.3.3)

AMF → NG-RAN: NGAP Paging
NG-RAN → UE: RRC Paging
UE → AMF: Service Request (via gNB N2)

UE-Initiated Deregistration (§4.2.2.3.2)

UE → AMF: Deregistration Request
AMF → SMF: Release All PDU Sessions
SMF → UPF: N4 Session Deletion
AMF → UE: Deregistration Accept

Packet Snapshot (deep decode with full IE tree + hex)

PRESET: DURATION:

#	Proto	Info

IE Tree

Select a packet…

Hex Dump

—

Saved Flows (capture → save → replay)

On the Call Flow (Ladder) tab, click Save Current Flow to persist what you captured. Saved flows can be shared by copying the JSON.

Total: 0

Name	Captured	Events	Size

Live 3D Topology (drag to rotate · scroll to zoom · packets animate in real time)

Active flows: 0

NGAP NAS SBI GTP-U

AI 5G Expert Assistant

Rule-based expert system with live lab context. Ask about procedures, failures, NFs, cause codes, slicing.

Missions — Prove you can run a 5G core

0 XP

Stress Test — Multi-UE Load Generator

Spawns N parallel nr-ue processes with auto-provisioned IMSIs. Each triggers a full Registration + PDU Session flow. Use the Ladder or 3D tab to watch the storm.

UEs: Slice:

Live session metrics

Per-NF Live Sparklines

Each tile shows a 60-sample rolling memory trace for every Open5GS NF.

Anomaly Detector (rules engine)

Runs every 10 seconds. Rules check NF health, error bursts, memory pressure, registration reject rate, N3 traffic, NGAP session state.

Copied to clipboard

PCAP Capture Manager

Capture Preset

SCTP / NGAP

N2 interface signaling

GTP-U

N3 user plane data

SBI (HTTP/2)

NF service-based interface

UPF Tunnel

ogstun interface traffic

All Traffic

Capture everything

Recording SCTP/NGAP

Duration 00:00

Size 0 B

File --

Saved Captures

No captures yet. Start one above.

Command Reference

System & Server

hostname

Show server hostname

uptime

Show system uptime and load

free -h

Display memory usage

df -h

Show disk space usage

ip addr show

Display all network interfaces

Open5GS Services

systemctl status open5gs-amfd

AMF - Access and Mobility Management

systemctl status open5gs-smfd

SMF - Session Management Function

systemctl status open5gs-upfd

UPF - User Plane Function

systemctl status open5gs-nrfd

NRF - Network Repository Function

systemctl status open5gs-ausfd

AUSF - Authentication Server Function

systemctl status open5gs-udmd

UDM - Unified Data Management

systemctl status open5gs-udrd

UDR - Unified Data Repository

systemctl status open5gs-pcfd

PCF - Policy Control Function

systemctl status open5gs-nssfd

NSSF - Network Slice Selection Function

systemctl status open5gs-bsfd

BSF - Binding Support Function

for svc in amfd smfd upfd nrfd ausfd udmd udrd pcfd nssfd bsfd; do sudo systemctl restart open5gs-$svc; done

Restart ALL Open5GS services

Configuration Files

cat /etc/open5gs/amf.yaml

View AMF config (PLMN, TAC, NGAP)

cat /etc/open5gs/smf.yaml

View SMF config (UE IP pool, DNS)

cat /etc/open5gs/upf.yaml

View UPF config (GTP-U, subnet)

ls -la /etc/open5gs/

List all config files

nano /etc/open5gs/amf.yaml

Edit AMF config - now writable, no sudo (apply: sudo systemctl restart open5gs-amfd)

UERANSIM (gNB & UE)

/opt/UERANSIM/build/nr-cli UERANSIM-gnb-999-70-1 -e amf-list

Check home gNB to AMF (N2). gNB runs as a managed service.

Start / restart the home gNB (RAN) and watch it re-run NG Setup with the AMF. Managed service - no duplicate gNBs.

ue-watch

Start UE from anywhere - full call flow + data tunnel (ue-watch = cd /opt/UERANSIM && ./build/nr-ue -c config/watch-ue.yaml)

cat /opt/UERANSIM/config/open5gs-gnb.yaml

View gNB configuration

cat /opt/UERANSIM/config/open5gs-ue.yaml

View UE config (IMSI, Key, OPc)

ps aux | grep nr-

Check running UERANSIM processes

sudo pkill -f nr-ue.real

Stop the UE (gNB keeps running - managed service)

Network Testing

ip addr show uesimtun0

Check UE tunnel interface

ue-ping -c 4 8.8.8.8

Ping the internet through the 5G data plane

ue-curl ifconfig.me

Public IP seen through the 5G data plane

ue-trace 8.8.8.8

Traceroute through the 5G data plane

Logs & Monitoring

journalctl -u open5gs-amfd -f

Follow AMF logs

journalctl -u open5gs-smfd -f

Follow SMF logs

journalctl -u open5gs-upfd -f

Follow UPF logs

tail -f /var/log/open5gs/*.log

Follow all log files

grep -i error /var/log/open5gs/*.log

Find errors in logs

Packet Capture & Debug

sudo tcpdump -i any sctp -w /tmp/sctp.pcap

Capture SCTP (N2/NGAP)

sudo tcpdump -i any port 2152 -w /tmp/gtpu.pcap

Capture GTP-U (N3 user plane)

tshark -i any -f sctp -Y ngap

Live decode NGAP

ss -tlnp | grep open5gs

Show Open5GS ports

MongoDB / Subscribers

mongosh open5gs

Connect to Open5GS database

db.subscribers.find().pretty()

List all subscribers

NAT & Routing

sudo sysctl net.ipv4.ip_forward

Check IP forwarding

sudo iptables -t nat -L -n -v

Show NAT rules

ip route

Show routing table

Troubleshooting

sudo pkill -9 nr-gnb; sudo pkill -9 nr-ue

Force kill UERANSIM

sudo ip link delete uesimtun0

Remove stale UE tunnel

dmesg | tail -50

Check kernel messages

sudo systemctl daemon-reload

Reload systemd