Removing a Public IP Address from a Linux Server (Ubuntu)

To remove a public IP address from a Linux server, proceed as follows.

Requirement

You have unassigned the additional public IP address in the Cloud Panel.

Log in to the server as an administrator.
To remove the additional IPv6 address, you must specify in /etc/network/interfaces to delete the following entries:

# The primary network interface
allow-hotplug ens192
iface ens192 inet dhcp
# IPV6 Setup
iface ens192 inet6 static
accept_ra 0
address MAIN IPv6 ADDRESS
netmask 64
gateway fe80::1
iface ens192 inet6 static
accept_ra 0
address additional IPv6 ADDRESS
netmask 64
gateway fe80::1

Example:

vi /etc/network/interfaces

# The primary network interface
allow-hotplug ens192
iface ens192 inet dhcp
# IPV6 Setup
iface ens192 inet6 static
accept_ra 0
address 2001:ba0:2020:1cc:3fe0:4d12:cd52:491a
netmask 64
gateway fe80::1
iface ens192 inet6 static
accept_ra 0
address 2001:ba0:2020:1cc:b62d:b9ef:e843:a0c1
netmask 64
gateway fe80::1

To restart the network, enter the following command:

/etc/init.d/networking restart