I'm going through OpenStack https://docs.openstack.org/devstack/latest/guides/multinode-lab.html (tutorial)

In the subsection "Set Up Ssh" it says "Set up the stack user on each node with an ssh key for access". Do I need to spawn up the worker nodes (VMs) myself rather than using the cluster controller to spin up the worker nodes?

If I need to spin up the workers nodes myself, I suppose I need to give them the following IPs (for example):

auto eth0 iface eth0 inet static
    address 192.168.42.129
    netmask 255.255.255.0
    gateway 192.168.42.1

and

auto eth0 iface eth0 inet static
    address 192.168.42.130
    netmask 255.255.255.0
    gateway 192.168.42.1

Furthermore, what is the role of the gateway?

It's like a jump node or something?