Ganglia monitoring fails when VMs don't have public IPs and/or hostnames

[tcrivat]

The Ganglia monitoring system does not work correctly in a cloud where the VMs don't have public IP addresses and/or public hostnames. In such a case it seems that the Ganglia system uses the local hostname which may not be unique and cannot be resolved to an IP address outside the VM.

This affects the PHP autoprovisioning module and the performance statistics in the MySQL (former known as Galera) service.