Hello Till, thank you for your feedback.
I have an instance of the Amazon, is applied to only one IP.
For ISPconfig work is necessary to create interfaces or network can do with virtual network interfaces?
AWS - Amazon
# Device: eth0
iface eth0 inet dhcp
New virtual interfaces
# Device: eth0: 0
iface eth0: 0 inet static
gateway 222 333 222 333
Then just add the IP in ISPconfig panel