For all the examples we are assuming you are changing the address from 192.168.1.2 to 192.168.2.2

Change /etc/network/interfaces/

Change the Address and Gateway in /etc/network/interfaces/ Example

Before:

address 192.168.1.2/24
gateway 192.168.1.1

After

address 192.168.2.2/24
gateway 192.168.2.1

Change /etc/hosts

Change the Address in hosts file

Before:

192.168.1.2 pve.localhost pve

After

192.168.2.2 pve.localhost pve

Change /etc/resolv.conf for new name server

Do this if you also changed the address for nameserver

Before:

search localhost
nameserver 192.168.1.1

After:

search localhost
nameserver 192.168.2.1

Loading New Network Config

reboot and your server should have the new ip address