Para liberar e renovar o endereço IP:
sudo dhclient -r eth0
sudo dhclient eth0
Ou você pode tentar um one-liner que pegue o nome padrão da ethernet de netstat
:
NIC=$(netstat -r | awk '/default/ {print $NF}'); sudo dhclient -r $NIC && sudo dhclient $NIC
Na% man_de% manpage:
-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.
Espero que isso ajude!