networking - Do all servers have one base OS, like in RED HAT openstack architecture?

Question

I'm a noob learning openstack. And The resources are all over the place tbh. I came across this image and would like to know one thing, So, Suppose I have 100TB of storage and 10 server grade processors, and ram of 1TB, do all these resources make up of only one base OS- RED hat enterprise Linux? So, they sell resources to connect all the equipment and connect to install one single OS which can comprehend them all? And Upon this, we throw an Openstack architecture so clients can use them as needed? Do we need as many NICs or the NICs virtual?

question from:https://stackoverflow.com/questions/65862267/do-all-servers-have-one-base-os-like-in-red-hat-openstack-architecture

Answer 1

How to scale?

As you say, you just add a server. Install RHEL or another supported Linux distro (it's best to install the same distro and version on all servers), then OpenStack and configure it. The new server will register with the OpenStack controllers and can be used for launching virtual machines immediately.

The process is a bit more involved when you run a cloud with baremetal instances (i.e. you don't launch VMs but provision physical systems), but in principle it's the same.

by definition(at consumer scale-like one laptop) we need a network interface card for one IP

This is incorrect. You can configure multiple IP addresses on a single interface, even on your PC at home, even if that PC runs Windows.

An enterprise cloud requires connecting nodes to several networks. Usually, servers have several physical NICs, bond them together, and use VLANs or other multiplexing technologies to implement the networks. See this blog (five years old, but the principles still apply today, and it's well-written) for a good example of a real-world OpenStack network architecture.

Openstack uses one big special NIC

OpenStack can be deployed in many ways. It is not a shrink-wrapped solution. It can be used on servers with single NICs, bonded NICs, VLANs, normal networks, etc. Your statement is almost correct if you think of a typical deployment and a bond interface as a "big special NIC".

If you are interested to try this out at home, see the OpenStack installation tutorial. You will learn a lot.