Linux Mint 18.2 Cinnamon 64-bit (desktop mode, hands-on)
GNU/Linux Debian 9.2 Cinnamon 64-bit (headless mode, SSH)
How to release and renew IP address from the DHCP server (router) on these Linux systems?
I have found there is the following program listening on the network on both of them:
Quoting the man page:
-r Release the current lease and stop the running DHCP client as previously recorded in the PID file. When shutdown via this method dhclient-script will be executed with the specific reason for calling the script set. The client normally doesn't release the current lease as this is not required by the DHCP protocol but some cable ISPs require their clients to notify the server if they wish to release an assigned IP address.
So, the solution for all interfaces would be:
sudo dhclient -r sudo dhclient
Or, conveniently, for a specific interface, say
sudo dhclient -r eth0 sudo dhclient eth0
Of course, when SSH'ing into a server, you need to run both commands oneliner or write a script as per this answer.
dhclient -v eth0 worked for me on RHEL 7. (actually enp0s3 -- insert your own network interface) dhclient -r eth0 did not.