Instructions for installing static and dynamic IP address in Arch Linux

net_config.sh

# first, install netctl if not already installed.
sudo pacman -S netctl

# to find out network card name; check
ip link


### configuring Static IP address
# my network card name is enp0s3. Now, copy the sample network card profile
sudo cp /etc/netctl/examples/ethernet-static /etc/netctl/enp0s3
sudo nano /etc/netctl/enp0s3
# replace eth0 with your actual network interface name. enp0s3
# also chnage DNS to this DNS=('8.8.8.8' '8.8.4.4')
sudo netctl enable enp0s3
sudo netctl start enp0s3
# also you have to disable dhcp
sudo systemctl stop dhcpcd
sudo systemctl disable dhcpcd


### configuring DHCP
sudo cp /etc/netctl/examples/ethernet-dhcp /etc/netctl/enp0s3

# replace eth0 with your actual network interface name. enp0s3
sudo nano /etc/netctl/enp0s3
sudo systemctl enable dhcpcd
sudo systemctl start dhcpcd

# to verify check
ip addr