Issue – the OpenStack instances hostnames are not resolved at the moment by their floating IPs.
Fast solution – use PowerDNS
1. Boot an instance , assign it a floating IP, open tcp ports 22 8001 and udp port 53.
2. Install PowerDNS, the particular yum package is named pdns.
3. install the mysql backend for PowerDNS, its available as yum package as well.
4. Install MariaDB , set the proper configuration, the initialize it at the default location.
5. Set the pdns user, create the pdns database and create the tables needed.
6. Configure the pdns service to use the gmysql backend.
7. Create and user at the OpenStack MySQL able to connect from the floating IP subnet.
8. Grant that user select permissions on all nova.* tables.
9. At the PowerDNS