Steps I had followed to bring up 1 controller, 3 compute node Openstack (Train release) setup on Ubuntu 18.04.
Pre-requisites in Controller node
Nova – Compute services on Controller node
Nova – Compute services on Compute nodes
Neutron – Networking service – on Controller node
Neutron – Networking service on Compute nodes
Horizon – Dashboard – Controller node
Cinder – Block storage service – Controller node
Cinder – Block storage services – Storage Nodes
Operations
Openstack : Removing compute node/host
Source is primarily from openstack.org documentation on the net from the installation perspective. However couple of changes on having /dev/sdb created in the RAID, upgrading MariaDB from 10.1 to 10.5 version (challenges with installing neutron services) were some customizations I had done, and have captured the same in my online notes.