Setting the hostnames

To simplify communication between hosts, it is recommended that DNS or a local name resolver be used to resolve hostnames. Using a text editor, update the /etc/hosts file on each node to include the management IP address and hostname of all nodes:

10.10.0.100 controller01.learningneutron.com controller01
10.10.0.101 compute01.learningneutron.com compute01
10.10.0.102 compute02.learningneutron.com compute02
10.10.0.103 compute03.learningneutron.com compute03
10.10.0.104 snat01.learningneutron.com snat01 

On each node, use the hostname -f command to verify that the fully qualified host name is properly reflected:

root@controller01:~# hostname -f
controller01.learningneutron.com