First post after a long time. Hope you enjoy it.
This is something people usually ask me and I would like to share with all of you. This way you can spend more time with your family and less looking for an answer @google : )
Let’s start. Imagine you are building your own private cloud using openstack and you deploy the controller and compute nodes using puppet (foreman or packstack).
But then you deploy the first instance and realize the search domain is generic (usually openstacklocal or yourdomain) and the dns too. Of couse, you can modify the configuration on neutron and add the correct dns servers to every subnets (only valid for DNS). Or you can follow a best practice and predefine this configuration for the whole cloud. Please, find below 4 simple and tested steps on how to configure this on a icehouse openstack deployment. In this case is a lab composed of 2 compute nodes, 1 controller and 1 neutron networker server.
1) On Neutron Server, edit /etc/neutron/dhcp_client.ini and adapt the following parameters to your network:
# Domain to use for building the hostnames
# dhcp_domain = openstacklocal
dhcp_domain = yourdomain
# Comma-separated list of DNS servers which will be used by dnsmasq
# as forwarders.
dnsmasq_dns_servers = 18.104.22.168,22.214.171.124
2) killall dnsmasq
3) systemctl restart neutron-dhcp-agent.service
4) soft reboot instances