UPF fails to start

I am trying to deploy Free5GC as a part of the Nephio demo project.
Unfortunately UPF crashes after deployment with the following error:

    2024-03-27T12:03:13Z [INFO][UPF][Main] UPF version:
            free5GC version: v3.2.1
            build time:      2023-06-09T16:41:08Z
            commit hash:     4972fffb
            commit time:     2022-06-29T05:46:33Z
            go version:      go1.20.5 linux/amd64
    2024-03-27T12:03:13Z [INFO][UPF][Cfg] Read config from [/free5gc/config/upfcfg.yaml]
    2024-03-27T12:03:13Z [INFO][UPF][Cfg] (*factory.Config)(0xc0003d05f0)({
    Version: (string) (len=5) "1.0.3",
    Description: (string) (len=17) "UPF configuration",
    Pfcp: (*factory.Pfcp)(0xc0003e0fc0)({
            Addr: (string) (len=11) "",
            NodeID: (string) (len=11) "",
            RetransTimeout: (time.Duration) 1s,
            MaxRetrans: (uint8) 3
    Gtpu: (*factory.Gtpu)(0xc0003e1170)({
            Forwarder: (string) (len=5) "gtp5g",
            IfList: ([]factory.IfInfo) (len=1 cap=1) {
                    (factory.IfInfo) {
                            Addr: (string) (len=11) "",
                            Type: (string) (len=2) "N3",
                            Name: (string) "",
                            IfName: (string) ""
    DnnList: ([]factory.DnnList) (len=1 cap=1) {
            (factory.DnnList) {
                    Dnn: (string) (len=8) "internet",
                    Cidr: (string) (len=11) "",
                    NatIfName: (string) (len=2) "n6"
    Logger: (*factory.Logger)(0xc0003b4c00)({
            Enable: (bool) true,
            Level: (string) (len=5) "trace",
            ReportCaller: (bool) false

   2024-03-27T12:03:13Z [INFO][UPF][Cfg] 2024-03-27T12:03:13Z [INFO][UPF][Main] Log level is set to [trace] level
    2024-03-27T12:03:13Z [INFO][UPF][Main] starting Gtpu Forwarder [gtp5g]
    2024-03-27T12:03:13Z [INFO][UPF][Main] GTP Address: ""
    2024-03-27T12:03:13Z [ERRO][UPF][Main] UPF Cli Run Error: open Gtp5g: open link: create: invalid argument

UPF configuration file (upfcfg.yaml)

version: 1.0.3
description: UPF configuration

  reportCaller: false
  level: trace
  enable: true

  - cidr:
    dnn: internet
    natifname: n6

  nodeID: # External IP or FQDN can be reached
  retransTimeout: 1s # retransmission timeout
  maxRetrans: 3 # the max number of retransmission

  forwarder: gtp5g
  - addr:
    type: N3

cat /sys/module/gtp5g/version

uname -a
Linux upf-edge01-65948c686-s9pts 5.15.0-100-generic #110-Ubuntu SMP Wed Feb 7 13:27:48 UTC 2024 x86_64 Linux

Any idea on that?


If these doesn’t work, try to reinstall gtp5g:

$ cd <path-to-gtp5g>/gtp5g
$ sudo make uninstall
$ make
$ sudo make install

It seems that installation or reinstallation of gtp5g did the trick. Thanks

git clone -b v0.8.5 https://github.com/free5gc/gtp5g.git
cd gtp5g
sudo make uninstall
sudo make install

Good to hear!
Hope you enjoy the free5GC ~