Proxmox networking

I need some help on proxmox. I want to create a network in proxmox. However, i do not have any unused adapters left to attach it to the vm bridge.
I have tried to create an alias on one of the adapters, but that did not work. Is there any support for IP aliasing in proxmox? if this is not possible, has anyone got a suggestion on how to create a new network in such a situation? Help will be very much appreciated.

Fisrtly proceed with great caution, chganging these parameters can break your networking. Does your switch support VLAN’s ? If so this may be the best way to proceed. If you look in the both the debian and proxmov docs alies can be supported, but what are you trying to achieve ? look at some of the diagrams shown in this doc –