How to add New IP addresses in Plesk
1. Go to Tools & Utilities > IP Addresses (in the Resources group), and click Add IP Address.
2. Select the network interface for the new IP from the Interface menu. All network cards installed on your server are shown in this menu.
3. Enter the IP address and subnet mask in the corresponding box (e.g.18.104.22.168/16).
4. Select the type of the new IP address, shared or exclusive.