Need help with network setup

I need some tips on setting up some part of the networking stack.
I am not an ip newbie but this seems to be over my head.
So I have a running one on a server.
On the server I have a br0 with and I have a natted network with gw to
And every vm I make with a 10.1.1.x address works just nicely.

Now my problem.
My server provider has given me a /28 public IP address range that I can use for vms that need to be accessible from the outside world.
They demand that all outgoing traffic is routed via the main ip address of the server.
And now I want to add that range into sunstone. When I add the address range (so not using network and broadcast address from the provided range of numbers) and set the gateway to the servers own/main IP address I get no traffic.
I must be not seeing something simple but I just can’t seem to find it.
Maybe something with routing?

Any and all hints, tips and tricks are highly appreciated.


Hi Jeoren,

In some providers like Packet, that seems to have a very similar network requirements as your provider, we use a SDNAT driver. Look here for an overview.

The VM will have 2 NICs, the regular IP + NIC_ALIAS with an IP from the /28 network (you need to add EXTERNAL = yes in order for the drivers to install the nat rules…)

You can take a look here for a network definition in this scenario. Note that is in yaml format but its translation to the standard OpenNebula format is straightforward. Also note that in this example an IPAM driver is used to dynamically request the /28 prefix to the provider, in your case simply add the IP information of the /28 network.