i set up a static ip address on my pi 3 but after that the internet is not working. how can I change it to dynamic? or what should I do?
Set a 'reserved' ip address in your DHCP (router) server: It will always assign the same IP address to your Pi. It will act the same as a static address. No configuration in the Pi.
You must change the configuration file /etc/networl/interfaces.
for eth0 you must have a row like this one
iface eth0 inet dhcp
change the file, saveit and restart network service:
you can renew your ip address with dhclient
Of course you must have root privileges. Use
su - root or