Prerequisite:
Basic Network knowledge (VLAN and subnetting)
A Network card with at least 2 Ethernet ports.

For once, I’ll be using the WebUI to add an additional network.
This needs to be setup on each individual servers.

I’m virtualizing it, so I just added another port to each server, and created a virtual network for it.

Best practice is to bond two or more, and separate VMs, management, and storage network from each other. Preferably with VLANs as well.

You go to each node, select “Networking” and click on “Create”.
The ens33 and ens36 is my ports. What the name is, might differ for you.
This is what I filled in:

Then you apply the configuration afterwards.
You can also reboot the server.