Is setting up the private network ip mandatory?

Hello, on the installation page,

this is listed

is it mandatory for the below to be created, assuming the public ip of the server is static, and why is it mandatory, or would CE not install?

Assuming that a NIC identified as enp0s3 is free on your system, for example in Virtualbox use a Network adapter of type Internal Network, you can assign it an IP address in the preferred way:

• use the CLI, for example ifconfig enp0s3 172.16.0.10 up

• Use netplan.io and add these lines to file /etc/netplan/01-netcfg.yaml:

  eth1:
    dhcp4: false
    dhcp6: false
    addresses: [172.16.0.10/24]
  

then issue the command netplan apply