sudo apt-get -y update
sudo apt-get -y install git gcc g++ cmake go libmnl-dev autoconf libtool libyaml-dev
go get github.com/sirupsen/logrus

git clone https://github.com/free5gc/gtp5g.git
cd gtp5g
git checkout v0.3.2
make
sudo make install

mkdir build
cd build
cmake ..
make -j`nproc`

cd build/bin
./testutlt

# Uncomment lines under /etc/sysctl.conf as below
net.ipv4.ip_forward=1

sudo apt install iptables-persistent netfilter-persistent
sudo iptables -A FORWARD -j ACCEPT
sudo netfilter-persistent save
sudo systemctl enable netfilter-persistent
sudo systemctl restart netfilter-persistent

sudo systemctl stop ufw
sudo systemctl disable ufw

sudo apt install iptables-persistent netfilter-persistent
sudo iptables -t nat -A POSTROUTING -o <DN_Interface_Name> -j MASQUERADE
sudo netfilter-persistent save
sudo systemctl enable netfilter-persistent
sudo systemctl restart netfilter-persistent

# (Must) IPv4 forwarding
sudo sysctl -a | grep forward        # check sys rule
sudo sysctl -w net.ipv4.ip_forward=1

# (Recommend) Forwarding chain in iptables can forward packet
sudo iptables -A FORWARD -j ACCEPT

# (Recommend) Close ubuntu firewall
sudo systemctl stop ufw
sudo systemctl disable ufw

# (Optional) Using NAT for UE to access data network
sudo iptables -t nat -A POSTROUTING -o <DN_Interface_Name> -j MASQUERADE

cd build
sudo -E ./bin/free5gc-upfd

ls /dev/mqueue/
rm /dev/mqueue/*

sudo ip l del upfgtp