user@user-OptiPlex-5040:~/free5gc/src/upf/build/bin$ sudo ./free5gc-upfd -f ../config/upfcfg.test.yaml 
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/src/upf_init.c:164 UpfInit() Config: /home/user/free5gc/src/upf/build/config/upfcfg.test.yaml  UPF=Util
INFO[2022-02-01T21:38:55+05:30] Set log level: info                           UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/src/up/up_path.c:39 UpRouteInit() APN routes added, main routing table:  UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:202 KnetPrintRoutes() DstIp               Gateway        Iface     Priority RtProto   Type         UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 0.0.0.0 /0          192.168.22.1   enp4s0    20100    dhcp      unicast      UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 0.0.0.0 /0          25.0.0.1       enp0s31f6 20101    static    unicast      UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 25.0.0.0 /24        0.0.0.0        enp0s31f6 101      kernel    unicast      UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 60.60.0.0 /24       0.0.0.0        upfgtp0   0        static    unicast      UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 169.254.0.0 /16     0.0.0.0        enp0s31f6 1000     boot      unicast      UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 192.168.22.0 /24    0.0.0.0        enp4s0    100      kernel    unicast      UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 192.168.22.0 /24    0.0.0.0        enp4s0    100      kernel    unicast      UPF=Util
INFO[2022-02-01T21:38:55+05:30] /home/user/free5gc/src/upf/lib/knet/src/route.c:237 KnetPrintRoutes() 192.168.22.0 /24    0.0.0.0        enp4s0    100      kernel    unicast      UPF=Util

return value 0
INFO[2022-02-01T21:39:40+05:30] /home/user/free5gc/src/upf/src/n4/n4_dispatcher.c:105 UpfDispatcher() [PFCP] Handle PFCP association setup request  UPF=Util
INFO[2022-02-01T21:39:40+05:30] /home/user/free5gc/src/upf/src/n4/n4_pfcp_handler.c:929 UpfN4HandleAssociationSetupRequest() [PFCP] Association Setup Response  UPF=Util